PERSONALITY OF PLANTS

The Fuchsia has a Distinctive and Esthetic Manner.

PERSONALITY
OF PLANTS

By ROYAL DIXON and
FRANKLYN E. FITCH

New York
BOULLION-BIGGS
1923

Copyright, 1923, by
Boullion-Biggs, Inc.

All Rights Reserved

PRINTED IN U. S. A.

CONTENTS

To

EDWIN MARKHAM

and

ANNA CATHERINE MARKHAM

who live their poetry.

“That nothing walks with aimless feet;
That not one life shall be destroyed;
Or cast as rubbish to the void,
When God hath made the pile complete;
“That not one worm is cloven in vain;
That not a moth with vain desire
Is shrivel’d in a fruitless fire,
Or but subserves another’s gain.”

—Tennyson.

INTRODUCTION

“The natural world, so to speak, is the raw material of the spiritual. Therefore, ere man can understand the spiritual, he must understand the natural,” writes Thomas Gentry.

The authors of this book would go a step further and say that the natural world is the spiritual. Soul and body, ephemeral and material, on this plane of existence are ineffably bound together. If you would climb to sublime heights of ghostly exaltation, study first the grass at your feet. If you would unravel the mysteries of the universe, desert the cloistered hearth for the wonders of woods and meadows. Slow-thinking man will never understand the secret of his own existence, until he thoroughly understands the plants outside his window.

For one to examine dead, withered specimens and hope to understand Nature is as if a person should analyze hundreds of Egyptian mummies in order to acquaint himself with the human race. You must seek the flowers on their native heath and treat them as friends and equals. Too often is the human creature inclined to look upon members of the vegetable kingdom as things apart from the world of life—insensate beings which can be cut down and trampled without offense—mere “growths,” more akin to earth and stone than to himself.

As a matter of fact, among the many forms of matter which exist on this earth of ours, the only clear-cut division is between the organic and the inorganic. The primary characteristic which distinguishes a living creature from inanimate objects about it is, in the words of Arthur Dendy, its power of “reacting toward its environment in such a manner as to conduce to its own well-being; of controlling not only its own behaviour but also the behaviour alike of its fellow creatures and of inanimate objects, in its own interests, thereby maintaining its own position in the universal struggle for existence.”

If this, then, is the one characteristic which distinguishes all terrestrial life, it follows that all creatures from the unicellular protoza to man himself are intimately related, are all part and parcel of the same system, are recognizable by differences in degree but not in kind, and are all interesting manifestations of that mysterious thing we call life. No creature lives or dies to itself. The correlation of organisms in Nature is similiar to the correlation of organs in individual plants and animals.

If the reader will but face this fact, he will approach the study of Nature with a new reverence. He will recognize the oneness and kinship of all life.

It is largely the object of this book to explore the inner recesses of breathing and thinking plantdom—to take the reader beyond the limits of text-book botany into regions of sympathetic insight—to show how even human arts and sciences are unchangeably bound up with the lives and hopes of the grasses and flowers.

To do this comprehensively, it has been thought wise not only to indicate how plants think and act but to incorporate a broad general history of their race stretching back to their first appearance on the planet and carried forward to the Burbank creations. With this knowledge in hand, we are better equipped to approach that fascinating realm which touches on the intelligence, the spirituality, the mysticism, the psychic phenomena, the higher life of plants.

In all this, the manifest independence of plant life and purpose is convincingly apparent. The plants have their own lives to lead and their own evolutionary processes to carry on. They completed the conquest of the earth long before the first human being appeared on its surface. Out of approximately a hundred thousand species of flowering plants, it has been estimated that only two hundred and forty-seven render direct and important service to man, and of these, only about fifty-four are utilized by him to any great extent.

While today it is no longer the fashion to believe that plants were created for man’s sole benefit, yet it cannot be denied that, because of their physical limitations and inferior intelligence, the plants frequently become very docile servants of the human race, thereby thriving mightily and to their own great advantage. This is as it should be. It is a law of earthly life. The danger lies in the contempt which this servitude engenders in the consciousness of man, the master. The plants are inferiors but very wonderful inferiors. We should accord them the highest respect. We should accept our dominion over them as a favour of a beneficent Providence,—a priceless gift which it is criminal to squander or misuse.

CHAPTER I
Origin of Plants

“’Tis a quaint thought, and yet perchance,
Sweet blossoms, ye have sprung
From flowers that over Eden once
Their pristine fragrance flung.”

“In the beginning God created the heaven and earth. And the earth was without form and void; and darkness was upon the face of the deep. And the spirit of God moved upon the face of the waters. And God said, Let there be light: and there was light!”

There is no greater mystery than the mystery of creation. Nowhere is its story told more eloquently and more scientifically than in the opening words of Genesis. All the fruitage of centuries of research but reaffirms this ancient narrative.

In the early days of this planet, when its crust was scarcely hardened from the molten state, there reigned what might be called the age of water. The entire surface of the globe was covered with a sea of restless, moving liquid, overcharged with a heavy atmosphere of vapour, so dense that not a single ray of light could penetrate it. As the process of cooling went on, more and more moisture condensed out of the air, until finally the first ray of light reached the universal sea and terrestrial day began.

Here in this dim, watery world, about the time that the first land began to emerge from the deep, by some divine, mysterious agency, the first life was born.

No doubt it was one-celled, free-moving, and like modern Flagellates, partaking of the nature of both plant and animal.

Slowly, and in response to evolutionary promptings, simple aquatic plant forms began to develop from the primary single cells. Animal life may have begun a simultaneous development, but if it did, it did not become strong enough to make any impress on the geologic rock from which we draw our data.

Certainly the plants were in the ascendency. The mobile green Algae were characteristic of the time. It is a remarkable thing that though they are probably the progenitors of all that vast world of vegetable life which enriches the world today, the Algae have always gone on reproducing their own kind. Today we can watch, under a microscope, the activities of the first form of terrestrial life, born incalculable aeons ago.

Mayhap the earth would be peopled exclusively by Algae and similar forms today, if it had not been for a prehistoric accident. One day, the water suddenly receded from a bit of land and left some Algae in the mud behind it. Now, the Algae had always been used to plenty of water and they saw that unless they did some quick thinking, they were in danger of drying up and blowing away. Accordingly, by common consent, they secreted and surrounded themselves with a jelly-like mass capable of absorbing and holding water. The amphibious Liverworts and the Ricciocarpus Natans do the same thing today.

With the Algae successfully living in the mud, surrounded by their mucilaginous water-reservoirs, it was but a step for some enterprising individual to extend a portion of his own tissue in search of more water. By this simple act, the first root came into being, and lo! there were terrestrial plants.

It is to be noted that all development in the plant world is born of necessity. To the plants, dependence upon water, food and the impulse to reproduction may be ascribed the start of many a new form among them. In the more complex groups we seem to see a conscious striving for higher and better things, but the lowlier species often need the goad of circumstance to force them to attainment.

When the plants first emerged upon the land, a number of structural changes became necessary. Whereas in the marine world, water is absorbed directly by all parts of the plant, in land life special organs of absorption and conductivity must be developed. At first, the roots were mere rhizoids or hairs, aided by water-drinking leaves and tubers, as in the Mosses and Liverworts today; but it was not long before true root and vascular systems were evolved. Other changes which came with terrestrial life were greater rigidity of tissue and devices to guard against evaporation. Leaves were developed for the purposes of manufacturing starch by photosynthesis, spreading out into thin layers in order to present the greatest possible surface.

These lower land plants retained and still retain some characteristics of their aquatic ancestry, notably swimming spore cells, as in the Mosses. The formation of rigid cellulose about vegetable cells stops their movement, except when cilia or projections of protoplasm extend through openings in the cell walls. The Liverworts were probably among the first real land plants: their spores are non-motile and they have a massive, foot-like organ for the absorption of water.

To the liberality of Nature we must ascribe the development of the law which ties the plants to the soil. They started out as animals, but enjoyed such an abundance of food that it became unnecessary for them to go in search for it. Water and carbon dioxide, which formed their principal means of subsistence, were all about them; they settled down to a life of quiet ease. When Corals, Sponges, Oysters and other lower animals are similarly situated, they become as firmly rooted as any plant. Moreover, they have free-swimming larvae analogous to the active zoospores of certain members of the plant world.

The first land vegetation of the globe must have presented a curious spectacle. Imagine a forest consisting of endless repetitions of Algae, Fungi, Lichens, Liverworts and Mosses, with many forms of gigantic sizes. The fresh-water Algae early developed a clever device to save their race from extinction by drought. Certain cells in each plant became hard and devoid of water, presenting that phenomenon of suspended animation to be observed in many of the higher seeds. When drought overtook any particular plant, it died, but these special restive cells lived, and were carried about by the wind or other agencies until a new abundance of moisture called them out of their trance. As zygotes, they exist in the Nostoc today.

The first plants were non-sexual and propagated by cell division. They were therefore capable of little advancement. With the introduction of the sex element, infinite possibilities for racial improvement and differentiation were opened up. The Mosses and Ferns belonging to the family Archegoniatae early established an alternation of generation in which the spores give rise to a small plant which looks like a Liverwort and bears the reproductive organs. The fertilized ovum of this plant grows into a leafy, sexless individual which produces spores non-sexually. We therefore have a generation endowed with sex organs making for development and progress, alternating with a sexless generation calculated to continue the tendencies of the race.

It is undoubtedly the sex element which accounts for those “sports” or mutations in plantdom which occasionally overstep the limits of species to form new species.

In the luxurious atmosphere of the early globe, vegetation waxed strong and vigorous and attained remarkable proportions. The primeval woods served to draw the superabundant carbon from the air and in millions of decayed bodies store it up as graphite, coal, petroleum and illuminating gas. The present day graphite beds alone represent vast quantities of ancient vegetation. It is a unique experience to be able to write or draw pictures of these prehistoric plants and use, in the carbon of our pencils, portions of their very bodies.

Everything was on a grand scale in the “Old Red Sandstone” age. There were no real trees yet, but the Asterophyllites, with their tall, slender stems, looked much like Palms. The Eryptogams were immense Mushrooms. Algae, Zostera and Psilophytons covered the shores with a tangle of seaweed vegetation.

In the succeeding carboniferous period, the plant world reached the climax of its dominion. While the variety was still very much limited, its vigor and luxuriance were astounding. The Tree-ferns seem to have come down to us unchanged from that time, but other plant descendants have dwindled in size greatly. Our humble Mares’ Tails were then twenty or thirty foot trees called Calamites. The Club-Mosses were giant Lepidodendrons. Other immense plants which have no direct descendants were the Sigillarias and the Lomatophylos. With its flexible, fluted and checkered stems, saw-edged leaves, and hanging garlands of parasitic Ferns, the carboniferous forest presented a remarkable scene.

The air was still very moist, covering the entire earth with a permanent fog and a uniform temperature. It is said that certain present-day islands in the Pacific Ocean approximate these ancient conditions.

All the plants of that time were flowerless, and belonged to neither the monocotyledonous nor the dicotyledonous classes, which include the greater number of families today. Thanks to many excellent specimens found in coal mines, it is possible for scientists to classify as many as five hundred families. It is believed that coal itself was mostly formed from small plants, but often entire trunks of the tree-like forms are found in bituminous strata. Bits of bark, cones and petrified leaves have also been unearthed at different times.

In the course of evolution, the Conifer trees were the next to develop extensively. They gained a great ascendency, but were succeeded by Palms, Alders, Cypress and Elms. By the Miocene period, all the forms known in tropic Africa today had come into existence, but were restricted by no such regional limitations as they labour under now. Oaks and Palms, Birches and Bamboos, Elms and Laurels grew side by side. The Palms reached as far north as Bohemia, Switzerland and Belgium. Maples, Lindens, Planes, Spruces, Magnolias, Persimmons and Pines flourished in Greenland. The Silver Fir and the Southern Cypress advanced to within two hundred leagues of the North Pole. The California Redwoods and Sequoias are survivors of a race which flourished in this age.

Man came very late in the earth’s evolution, but he has had a profound effect upon the plant world. His most noteworthy feat has been to take comparatively weak plants like the grains and, for his own purposes, give them large areas in which to grow. Wheat, Maize, Yams and Tobacco became widely diffused as cultivated plants before the historic era. It is probable that Rice and the Legumes were first domesticated in Asia; Barley and Wheat in Egypt; and Maize, Potatoes, Yams and Manioc in America.

The origin and development of plants is a fascinating study. So authentic are the records which they have left in the eternal rocks that we have little difficulty in reconstructing their entire race history.

THE LIFE OF A DAISY IS SPENT IN BRIGHTENING OUR FIELDS AND PASTURES

CHAPTER II
LIFE OF A PLANT

“We cannot pass a blade of grass unheeded by the way,
For it whispers to our thoughts and we its silent voice obey.”

—J. E. Carpenter

The growth and development of a plant, though such a common thing, is full of very real wonder and mystery. It takes only a little observation to discover the various stages in the process, but how they are brought about and by what laws they are governed, not even the most astute investigators can always say.

To the lay mind, the statement that the plants depend upon the soil for their nourishment is quite self-evident, yet it is extremely inaccurate. It is now quite certain that the vegetable world relies upon the air for its largest and most important food supply. The great mass of carbon which is the chief constituent of all plant structure is drawn almost exclusively from the atmosphere. While it is true that many vital elements are obtained from the earth, all green plants manufacture the greater part of their solid material out of the carbon dioxide of the air. Of what the plants do obtain from the soil, water makes up the largest bulk. The bread and meat of the plant world is carbon dioxide; the drink is soil water in which is dissolved certain essential salts and condiments.

A chemical analysis of a Green Pea will show approximately 46.5% of carbon, 4.2% of nitrogen and 3.1% of all other elements, exclusive of the hydrogen and oxygen which make up the water permeating all tissue.

This is truly a startling fact. Instead of belonging to the earth, the plants then belong primarily to the air. The air is their natural habitat; the earth serves to give them a fixed place in the world and provide them with flavoured water to drink.

Plants are born from seeds, the joint product of two previous individuals; they live by eating and drinking; they marry and in turn rear families of their own. It is our purpose in this chapter to show, in a very definite way, that this is not mere figurative language but a common-sense statement of fact.

The cycle of plant life can be illustrated by any dicotyledonous, herbaceous annual. If one is so inclined he may hark back to his high school days and plant a few Beans in a box as a practical illustration of the facts stated here.

The first action of the planted Bean is to absorb water to a prodigious amount, and so wake the quiescent life forces which may have been slumbering within it for years. It is a law of animal and vegetable life that all vital processes must be performed in solution. Without water, life is dead or somnolent.

When Nature made the Bean, she left a small opening or window in its skin-wall called the micropyle. Through this opening of the water-swollen seed, now issue two pale sprouts. One is long and pointed; it is the radicle or incipient root. The other is stubbier and is tipped by a cluster of folded, yellow-green leaves; it is the plumule or incipient stem. With unerring exactness, the radicle grows down into the soil and the plumule feels its way up into the air.

By this time, the seed has burst its walls and split into two halves, which indicates that it belongs to the dicotyledonous group of plants. As the seedling continues to grow, these cotyledons begin to shrink and shrivel. The plant is living on their substance until it can begin to make its own. In the case of the Bean, the stem lifts the emaciated cotyledons up into the air, where they act as leaves until the tiny green things at the stem’s tip have expanded into those important organs.

When the first leaves have fully opened and the spent cotyledons have dropped off as mere empty shells, the independent life of the plant may be said to have begun. We are now in a position to examine its methods of living.

Examining the root, we find that by this time it has expanded into many branches. Each tip is a tiny mouth through which the plant drinks the all-important water and mineral salts. Root tips exercise great ingenuity; they feel their way underground, touching here, recoiling there, and searching out the elements necessary to the plant’s economy with wonderful sagacity.

The actual absorption is done by minute filaments or hairs which take in water and its dissolved contents by osmotic action. They secrete a digestive fluid which renders certain minerals soluble, and by a strange intelligence, select the kind and amount of material they take in. In certain groups of plants, notably the Legumes, colonies of Bacteria take the place of root hairs, and by a reciprocal action, provide the plant with the nitrogenous elements which it craves.

The principal food of most vital importance taken in by the roots is nitrogen. Nitrogen is one of the basic elements of protoplasm, the life fluid of the living cell. Where there is life, there is nitrogen. Sulphur, phosphorous, silica, iron and other elements are also needed in small quantities.

The root hairs are constructed so as to allow fluids to pass in but not out. The continual absorption of water results in a mechanical pressure which automatically forces the sap up through the stem to all parts of the plant. The process is aided by the evaporation of water from the leaves, through the partial vacuum created by them at the top of the system. Pushed from below and pulled from above, the sap of a tree, for instance, moves with a propulsive power greater than the blood pressure of the strongest animal.

Above the roots and the stem of the developing plant are the branches. Their function is too well known to need much comment. They raise the leaves up into the air and the light. They act as conduits for ascending and descending sap. They give the plant strength and rigidity. Each main stem is a clever bit of plant engineering, so built as to withstand all kinds of heavy strains and stresses.

The leaves of our seedling are extremely important parts of its anatomy. Pluck them off and it will die in a few hours. They are mouths, stomachs and lungs all in one. Their surfaces are broad and flat, in order that they may catch and devour every particle of carbon dioxide which comes their way. To us, carbon dioxide is a negligible part of the atmosphere, but out of this intangible product of combustion, arising from fires, breathed out by animals and expelled by volcanoes and hot springs, the tallest tree builds its greatest structure. Is it any wonder that it takes so long!

In the inner tissue of each leaf is a substance called chlorophyll. It is the material which gives leaves their green colour. It is one of the most important substances in plantdom. Under the influence of sunlight, this chlorophyll takes the carbon dioxide of the air, and, with water and certain minerals, makes starch, the raw material of plant construction. This process, called photosynthesis, goes on while the sun shines, and stops with the approach of darkness. The necessity of plenty of light cannot be overestimated.

In the manufacture of starch, oxygen occurs as a by-product. As the plant has no use for this element, it is breathed out from the surface of the leaves. From the standpoint of man, this makes plants atmospheric purifiers. At night, when the making of starch is suspended, there is often a superabundance of carbon dioxide within plant structures. It is this gas which is now exhaled, though in very small amounts. Some authorities maintain that the excess of carbon dioxide is contained in water absorbed by the roots. In the daytime this is welcomed as additional starch material, but at night there is no use for it.

Another substance which is always present in excess of plant needs is water. It is essential as a tissue builder and also as a carrier of nourishment. Its continual evaporation from the leaf surfaces furnishes one of the sources of motive power for the circulatory system. The rate of evaporation is controlled by the stomata, little pores or mouths which have contractible lips. In the Lilac there are as many as one hundred and twenty thousand stomata to the square inch. They are nearly always located on the under surface of the leaves.

Certain plants like the Cacti seem to be able to get along without leaves, but thick, fleshy sections of stem perform all their functions. The Fungi and other parasites differ from most plants in that they have no chlorophyll for starch-making but live on the already elaborated tissue of living or dead neighbors.

When our seedling grows old enough, it marries and has a family. Among the higher plants, the sexes are quite distinct. There are such things as male plants and such things as female plants, but more often both sexes occur in the same individual and frequently in the same flowers. The Hop, Nettle, and Date Palm are one-sex plants. Maize has flowers of different sexes on the same stem.

Flowers are the reproductive organs. In the blossom of the Bean, the stamens are the male organs and the pistil is the female organ. The stamens produce dust-like pollen which is conveyed by the wind to the pistil of some other flower. Pollen grains deposited on the stigma of the pistil are held there by a sticky secretion until they can grow a long tube which travels down the style, eventually reaching and fertilizing the tiny ovules or eggs.

The ovules then develop into seeds and the pistil grows into a pod, on both of which the parent plant bends all its energies to give a good start in the world.

The cycle is now complete. We have another Bean and are back to where we started, ready for some other fellow to plant the new Bean and perform the experiment all over again.

This is the story in brief, but there are many other details. The different plants have invented and perfected all kinds of devices to secure the effective propagation of the race. The Hazel and the Grasses hang their stamens out in the wind in order that it may blow their pollen to some other plant, which is waiting with feathered pistil to catch it. Most garden plants depend on the insects to act as pollen carriers and display gorgeous flower-petals and nectar pits with which to attract them. Many plants aim to prevent self-fertilization by having the stamens and the pistil come to maturity at different times.

The plants go to great lengths to secure an advantageous distribution of their offspring. The nature of a plant is to live by growing. When it has reached a prescribed height, it must continue the process by producing new individuals to carry on the cycle. It gives its children a start in the world by providing them with wings, bladders, feathers, spikes, thorns, sticky secretions, submarines, boats, and kites, according to the method of travel they are to use. Sometimes the matured pistil or fruit is dispersed entire. Sometimes it opens and shoots the seeds out. The Violet and Oxalis act like veritable guns, so vigorously do they expel their seeds. There are seed-capsules, like those of the Primrose and Xanthium Spinosum, which open at the top so that only a high and efficient wind can dislodge the seeds.

The problem of food storage is an important one in plantdom. Annuals die when they have flowered and produced seed. Perennials wither but persist for a number of seasons and sometimes many years. Those whose stems or trunks are permanent withdraw their starch and chlorophyll into their cambium layer where it is safe from freezing. Those which die down to the ground each fall store up food material in underground stems and roots in sufficient amount to get a good start the following season. The Potato is an enlargement of the underground stem, but Carrots, Beets, and Turnips are bulbous roots. Hyacinths, Tulips, Daffodils, Snowdrops, Crocuses, and Buttercups all store food material in bulbs. Practically all wild flowers which come up early in the spring, feed upon the nutriment manufactured during the previous season.

Buds represent the foliage of the coming season. Each fall, trees and bushes prepare for next year’s growth by putting forth miniature shoots and leaves folded up in warm brown overcoats. At spring’s urgent call, the buds have merely to cast aside their coverings and step out into the warm sunlight. These buds really make a tree a community of individuals, because each one is capable of reproducing everything that has occurred on the plant up to that point. This is the principle on which grafting is carried on.

The most wonderful thing in all plant structure is the plant cell. There are anywhere from six thousand to twelve thousand of these living units to the square inch. In their restless, moving protoplasm lies the mystery of life—the directing energy which controls the plant’s activities and makes it a conscious, intelligent organism.

IF THIS AGED CEDAR COULD TELL ITS LIFE’S STORY, WE WOULD FIND IT FULL OF ROMANCE AND ADVENTURE

CHAPTER III
Migrations of Plants

“Race after race of leaves and men
Bloom, wither and are gone;
As winds and water rise and fall
So life and death roll on.”

We are so in the habit of thinking of plants as fixed and static things that it rarely occurs to us that they migrate over the earth’s surface quite as extensively as do men or animals.

While it is probably true that vegetation originated simultaneously at different points on the globe’s surface, not much observation is necessary to indicate that it does not always stay where it is put. Plants are peculiar and native to certain lands in a very definite way, but their love of adventure often carries them to the far corners of the earth. They are the most energetic and effective colonizers in existence. The complete history of plantdom would include the stories of invasions, conquests and revolutions quite as stirring as anything in human annals.

If it is absorbing to follow the racial movements of man, ancient and modern, it is equally fascinating for a lover of plants to investigate their migratory habits. We have exact records of many of their travels and can make interesting conjectures about the rest.

To a layman, the present distribution of plants may seem chaotic. He reads that certain families are natives of Europe and Australia, or North America and Africa and are absent from all intervening countries. The Alpine species Primulas and Saxifrages are common to both the Arctic and the Antarctic. There are fifty-eight European and New Zealand species which are identical. The British Grass Poa Annua is also found in the Andes of Brazil. Through what thousands of years of change and evolution have these things come about! Yet the results are no more complex than was the filling of America with its mixed and conglomerate human population.

In a general way, there is a measure of fixity to plant distribution. Certain plants have elected the tropics as their home; and only under the greatest stress of circumstance can they be induced to go elsewhere.

Tropical heat and moisture make for luxuriance of vegetation. There is a much greater variety there than in the North. Woody Vines climb the tallest trunks, where they intermingle their leaves and blossoms with those of their host. Gorgeous Air Plants beautify and perfume the forest. Stately Palms wave magnificent bouquets of pendulous fronds.

As we travel away from the equator, the vegetation takes on a simpler aspect. There are more annuals and more herbs. The number of Ferns, Grasses, and catkin-bearing Trees, like the Alder and the Birch, increase. The limited growing seasons make for a more restricted accumulation of tissue. Such tropic plants as have braved the rigours of the colder climates have dwindled much in size. The Castor Oil Tree becomes a humble annual (Ricinus Communis) only three to eight feet in height. Other tropical trees become so small that temperate zone folk tread them under foot.

When we get into the polar regions, all the plants take on a stunted and dwarfed appearance and, in some cases, retire almost entirely under ground. The number of genera and species is much reduced. The Oak, Walnut, Chestnut and Elm are replaced by the hardy conifers. At the point where vegetation becomes almost extinct are dwarf Birches, Willows and polar Blackberries (Rubus Arcticus). The simple Mosses and Lichens mark the last lingering evidences of life.

A curious feature of plant life in the polar regions is the rapid growth which it often exhibits. The summer of the Far North is short but it is one day of intense and blinding light. The sun shines continually throughout each twenty-four hours. By virtue of its stimulating power, plants are able to perform in a few weeks processes of development which take months under ordinary conditions.

It is illuminating to take a single country in a more favoured climate and, as far as possible, trace its plant history. The British Isles, because of their limited area, are a convenient field of study. An investigation of their settlement by plants gives us many hints about prehistoric climatic and geographical changes.

Geologists generally believe that the British Isles were once joined to the mainland of Europe. It was at this time that they were settled by vegetation. Some of this plant life came from Spain and some from southwest France; there was also a Germanic group. The floating ice of the glacial period brought over hardy visitors from the Scandinavian peninsula. A few plant immigrants arrived from North America and landed on the west coast of Ireland.

St. Helena is an isolated volcanic mass built up seventeen thousand feet from the bed of the ocean. It therefore has its own peculiar vegetation, a portion of which is believed to have been evolved on the spot from the one-celled state. According to Sir Joseph Hooker, forty out of fifty flowering plants and ten out of twenty-six Ferns “with scarcely an exception cannot be regarded as very close specific allies of any other plants at all.” Sixteen of the Ferns are common to Africa, India or America and were probably carried there by the wind. Ocean currents also brought other species from Africa.

In 1883, a most interesting thing occurred on the Asiatic island of Krakatoa. A violent volcanic eruption wiped every vestige of life off its surface. When the flow of lava ceased and the earth cooled once more, Krakatoa was to all intents and purposes a volcanic island newly risen from the sea. It presented the exact analogy of a recently created bit of land waiting to be settled by the plants. In 1883, it was as barren as the face of the moon. In 1888, a Mr. Hemsley described its appearance as follows:—

“The first phase of the new vegetation, was a thin film of microscopic fresh-water Algae, forming a green, slimy coating, such as may often be seen on damp rocks, and furnishing a hygroscopic condition, in the absence of which it is doubtful whether the Ferns by which they were followed could have established themselves. Both Algae and Ferns are reproduced from microscopic spores, which are readily conveyed long distances by winds. Eleven species of Ferns were found, all of very wide distribution, and some of them had already become common the fourth year after the eruption. Scattered here and there among the Ferns were isolated individuals of flowering plants, belonging to such kinds as have succulent seed-vessels eaten by birds, or such as have a light, feathery seed-vessel like the Dandelion and a host of others, and are wafted from place to place by the winds.

“On the seashore there were young plants and seeds (or seed-vessels containing seeds) of upwards of a dozen other herbs, shrubs and trees, all of them common on coral islands, and all known to have seeds capable of bearing long immersion in sea water without injury. Among the established seedlings were those of several large trees, and a Convolvulus that grows on almost all tropical coasts, often forming runners one hundred yards in length. There were Cocoanuts also, though none had germinated.”

The farther such an island is from the land, the longer will vegetation take to get established. Darwin found that the isolated islands of Keeling, after thousands of years of existence, contained only twenty kinds of flowering plants.

Although plants have no legs they are not devoid of mobility. When man uses the propulsive power of steam to travel by, he shows no greater ingenuity than do plants in their use of special devices of locomotion.

Species like the Tumble Weed (Amarantus Albus) pull up stakes, and, consigning themselves to the swift autumn winds, race across country at great speed, scattering seeds as they go. The Utriculariae or Bladderworts are true sailors and float about on inland streams like little ships. The Duckweeds and Wolffias also have aquatic habits.

However, most plants prefer to travel in embryo. In the form of small and microscopic seeds the force of gravity has little influence on them, and they can journey for long and incredible distances.

To this end practically every seed in existence is provided with some apparatus or appendage designed to help it make its way in the world. The Elm, the Linden, and the Ash bear winged seeds, which are so efficient in riding the breeze that they are really miniature aeroplanes. The double wings of the Maple are very much like those of an insect. The seeds are released from their container in such manner as to acquire a whirling motion as they fall.

The progeny of the Willow is provided with long projecting hairs which curl together to form a tiny balloon. Feathery attachments called pappus enable the children of the Dandelion, the Thistle and the Fire Weed to go on long jaunts of exploration.

The seed-pods of the Sycamore are great rollers. Even ordinary nuts and fruits may be blown to considerable distances by the strong winds of autumn. The many edible seeds and fruits are carried gratis by birds and animals. The Mistletoe, for instance, is distributed entirely by them.

Walnuts, Butternuts, and Acorns bear water travel well, as do certain of the hard seeds. The Arrowhead (Sagittaria) has a self-made water-wing on which its offspring float.

Plant seeds, which like to travel on animals, all provide themselves with grappling irons in the shape of sharp hooks, spurs and spines with which they cling to their carriers. Everybody in the northern United States knows of the avidity with which the Cockle-bur clings to any passing object. The Touch-me-not (Impatiens), the Wistaria, and a host of others, actually shoot their seeds from their pods as from a gun.

Every vagrant breeze, every purling brook, every deep river, every ocean current, is a highway of travel in plantdom. The birds, the beasts, the insects, and not least, man himself, are involuntary vehicles on which our vegetable friends tour the world. The spores of Mosses, Lichens, Fungi and other cryptogams are so light that they find no difficulty in mounting into the air and traveling across the Atlantic or Pacific Oceans at will.

The complete record of plant conquests would fill many volumes. Their operations have extended into every land and have had influence on the world’s history. It very often happens that plant invaders become so quickly and thoroughly naturalized in a strange country that they go a long way toward supplanting the original inhabitants in a very short time.

It was Darwin who first noticed the extensive conquests of the Cardoon Artichoke (Cynara Cardunculus) in South America. In one section, these prickly plants covered an area of several hundred square miles, having entirely superceded the aborigines.

It is well known that the most troublesome of the American weeds are of British origin. On the other hand, the American water weed Anacharis blocks up small English streams. The grass called Stipa Tortilis has captured the steppes of southern Russia. The love of change seems to be an inherent tendency in plantdom. The Pigweed and the Morning Glory have come north from the tropics. The Canada Thistle, originally a foreigner in North America, has spread all over Canada and New England. The American Erigeron Canadense has emigrated to all parts of the world. The flora of Scandinavia, like its people, are aggressive colonizers. More than one hundred and fifty species have reached New Zealand alone and nearly as many have established themselves in the eastern United States.

Some plants seem to be able to adapt themselves to any climate and therefore are born explorers, but the greater number are too fastidious regarding conditions of soil, heat, light and moisture to thrive well everywhere. It is a noticeable fact that the most successful plant invaders usually come in the wake of human colonizers and stick to the sphere of man’s influence. For example, the Butter-and-Eggs (Linaria Linaria) has followed the railroad tracks almost entirely over the tropical and semi-tropical world. Sometimes, however, hardy plants advance into the primeval jungle, there to give battle to its lusty inhabitants.

On the whole, annuals have a better chance than perennials to gain a foothold in a new country. Every spring the weeds, grasses, and common flowering plants have to start all over again from a seed beginning. The spores of newcomers, therefore, have almost an equal chance with the established inhabitants. On the other hand, the bodies of perennials occupy the land in close-packed ranks all the year, ready to dispute every inch of ground with an aggressor. It is very hard for new plants to gain entrance into a well-grown forest.

Man has been of tremendous aid in the distribution of plants over the earth’s surface. Either consciously or unconsciously he takes his plants with him wherever he goes.

It was the Emperor Chang-Chien who carried the Bean, Cucumber, Lucerne, Saffron, Walnut, Pea, Spinach and Watermelon from Asia to China about 200 B. C. The period of Roman conquest was a great epoch in the history of plant migrations. The Peach and the Apricot first became prominent as fruits at that time. Roman generals introduced the Pear, Peach, Cherry, Mulberry, Walnut and many ornamental shrubs into England.

From an obscure native of Bengal, the Sugar Cane has become an important plant of wide distribution. Coffee, a wild berry of Arabia, is now the chief crop of whole countries in the West Indies and South America. The yellow Maize of America has become a citizen of the world. The weak and humble Wheat is the sole possessor of thousands of square miles of land in America, Russia and elsewhere.

All this has been wrought by man’s efforts. When it is to his interest, he fights the battles of plantdom, and because of his superior knowledge and equipment is of tremendous service. Sometimes, however, he gives aid to his plant friends through motives that are quite unselfish. A romantic story is related of a French naval officer named Declieux who once elected to carry a Coffee Plant to the Colony of Martinique. The supply of water ran low during the voyage, and, rather than see the plant die, the man shared his daily glass with it, at considerate discomfort to himself.

Until man becomes all-wise, he will continue to make mistakes; and not least of these will be in connection with his investigations into the mysteries of Nature. It has happened more than once that he has introduced some new plant into an old land, or vice versa, and lived to thoroughly regret his action.

Sometime in 1890, a generously inclined individual threw a Water Hyacinth into the St. Johns River in Florida. In the space of a few short years, that single plant had multiplied so prodigiously as to seriously impede navigation, lumbering and fishing.

Jack London tells of a similiar thing that happened in Hawaii: “In the United States, in greenhouses and old-fashioned gardens, grows a potted flowering shrub called Lantana; in India dwells a very noisy and quarrelsome bird known as the Myna. Both were introduced into Hawaii—the bird to feed upon the cut-worm of a certain moth; the flower to gladden with old associations the heart of a flower-loving missionary. But the land loved the Lantana. From a small flower that grew in a pot, the Lantana took to itself feet and walked out of the pot into the missionary’s garden. Here it flourished and increased mightily in size and constitution. From over the garden wall came the love call of all Hawaii, and the Lantana responded to the call, climbed over the wall, and went a-roving and a-loving in the wild woods.

“And just as the Lantana had taken to itself feet, by the seduction of its seed it added to itself the wings of the Myna, which distributed its seed over every island in the group. From a delicate, hand-manicured, potted plant of the greenhouse, it shot up into a tough, and belligerent swashbuckler a fathom tall, that marched in serried ranks over the landscape, crushing beneath it and choking to death all the sweet native grasses, shrubs and flowers. In the lower forests, it became jungle, in the open, it became jungle only more so. It was practically impenetrable to man. The cattlemen wailed and vainly fought with it. It grew faster and spread faster than they could grub it out.”

Then ensued a battle royal between man and plant. The man called to his aid hosts of insect mercenaries. “Some of these predacious enemies of the Lantana ate and sucked and sapped. Others made incubators out of the stems, tunnelled and undermined the flower-clusters, hatched maggots in the hearts of the seeds, or covered the leaves with suffocating fungoid growths. Thus simultaneously attacked in front and rear and flank, above and below, inside and out, the all-conquering swashbuckler recoiled. Today, the battle is almost over, and what remains of the Lantana is putting up a sickly and losing fight. Unfortunately, one of the mercenaries has mutinied. This is the accidently introduced Mani Blight, which is now waging unholy war upon garden flowers and ornamental plants, and against which some other army of mercenaries must be turned.”

Such unfortunate occurrences are sure to become more and more infrequent as plant emigration and immigration finds itself under increasingly drastic governmental regulation.

The Foreign Seed and Plant Introduction Service of the United States Department of Agriculture makes a scientific examination of all plants brought into the United States for propagation purposes. It rids them of objectionable Bacteria and insect pests and refuses them admittance entirely if its experts decide that the newcomers will be harmful or injurious in any way.

The agents of the Service are constantly scouring the far corners of the earth for new and rare plants. In the twenty-four years of its existence it has introduced from abroad some fifty thousand specimens of seeds and plant cuttings. Some of the successful immigrants have been Feterita (from Egypt), Sudan Grass, Bamboo and Alfalfa. New Zealand has yielded new types of Potatoes. Dwarf Almonds and strange Cherries and Apricots have come from Turkestan. All these have proven of commercial importance, as has Durum Russian Wheat, credited with opening up new areas in the Northwest, and the Navel Orange from Brazil which has created for itself a California industry covering thirty thousand acres and valued at fifteen million dollars per annum.

Painstaking and scientific methods are best when man attempts to aid Nature in her evolutionary processes, especially when they are in connection with the migration and distribution of plants.

CHAPTER IV
Comrades of the Plant World

“... which links by a fraternal tie
The meanest of His creatures with the high.”

—Lamartine

The first and greatest problem for every terrestrial creature is to live. The chief means of doing so is to eat. Therefore, the relation of being to being and species to species is dominated by the necessity for food. Among man this fact is somewhat masked and obscured, but in the rest of the world it is entirely plain and obvious. Again and again on every hand, we see that plant, animal, and man all maintain their life impulses by consuming the tissue of their fellows.

In view of this fundamental fact, we can afford to look with some degree of charity upon that class of plants which are termed parasites. These interesting creatures are merely carrying out in a very direct and apparent way a principle which permeates all domains of life. A Tiger kills its prey; an Ox devours unoffending Grass; the parasitic Dodder robs some healthy neighbour of part of its juices.

The word “parasite” originally referred to a member of a college of priests who had their meals in common. Later, it came to mean living at another’s expense, as large numbers of people did in classical times. When one realizes that there are twenty-five hundred species of parasitical seed plants, he hesitates to brand them all as thieves and degenerates. Taking into consideration plants which depend upon the soil fungi for part of their sustenance, we should have to call half the seed plants in the world “parasites.” On a basis of strict accountability, it would also be necessary to classify all fruits as “parasites” as they draw nourishment from the parent boughs and give no return.

The fact is there are very few plants which are not more or less dependent upon some living fellow creature for their food supply. Sometimes the relation is strictly reciprocal; sometimes the advantage appears to greatly favour one or the other of the participants. In other cases the occurrence arises accidently through chance proximity, without a conscious pact or deliberate contract.

Edward Step in his illuminating book Messmates sums up the matter admirably: “Two friends in good health, each able to earn his own living, agree for the sake of companionship to live together, but each defraying the cost of his own necessities and luxuries. This is a case of mutualism. Two other friends also agree to share quarters and have a common table; but one may be infirm and wealthy whilst the other is strong and comparatively poor. The infirm one offers to pay two-thirds of their common expenses if the other will contribute one third, plus his protection, cheerful companionship or other valuable help. This is a commensalism. The pair are messmates, each contributing to hotch-potch according to his ability or endowment, each affording what the other lacks, and both, therefore, benefitting from the partnership.”

It must be admitted that there are cases of plant companionship in which, to all human perception, the material benefits seem directly one-sided, but who can conclusively deny that the nourishment-giving partner may not receive some psychic or spiritual benefit from the union? The Orchids and many other tree-parasites bear flowers of exquisite beauty. Can we be quite sure that the trees do not like to adorn themselves with gorgeous ornaments of this kind? Such a desire would be quite natural.

Plants which are low and weak in the scale of evolution are very prone to enter into symbiotic relations. The Lichens are compound organisms in which green Algal cells live between fungous threads. The Fungus sucks up the water and mineral salts from the soil and the Alga combines them with carbon dioxide from the air to form palatable food for both. Such plant-partners have been observed to live together amiably for twenty-five years or more.

The Fungi and all plants which are “pale, fleshy, as if the decaying dead with a spirit of life had been animated” have no chlorophyll, the mysterious green substance which is necessary for the production of starch. They must either make alliances with plants which possess this vital elixir or live on decaying matter which contains elaborated food material. Many choose the latter course, but a goodly number, especially those of primitive structure, have entered into profitable partnerships.

The minute one-celled plants called Zoochlorella or Zooxanthella have chosen the fresh water sponge Ephydatia Fluviatilis for their messmates. Sometimes they live with the Hydra called Viridis and impart to it a bright green colour.

There are whole regiments of microscopic parasites which thrive on living plant tissue and cause spots and rust to appear on Apples, Peaches, Pears and other fruits and number among their cohorts Rose-blight, Wheat-rust, and various Mildews. The larger messmate does not receive very much benefit from the relation, in this instance, except when the minute guests serve to cover a cut or an abrasion with a protective mantle, just as Mildew shields cheese or jelly from decay.

Cases where Fungi render very valuable services to larger plants are exemplified by the Monotropa or Indian Pipe. This pallid scavenger grows on the decaying vegetable matter of the woods. It toils not, neither does it make plant starch, but it is able to produce pretty, ghostly flowers and white scale-like leaves. On its roots thrive species of Fungi which perform the part of root hairs and in return receive nourishment from their host. Certain authorities claim that the Fungi get the better of the bargain, as the Monotropa has been known to maintain its health without them in laboratories. But the fact is the relation does exist with undisputed benefit to both parties.

Beech Drops germinate in contact with roots of the Beech tree, attach themselves there and raise yellow, seared stems covered with scales instead of leaves but bearing perfect flowers. The Broom-Rapes get their nourishment from the roots of Tobacco and Hemp in the same way.

Prominent among the larger parasitic plants is the Dodder or Devil’s Thread. This vine derives all its sustenance from other plants and, as far as can be determined, gives no material return. From this standpoint, the Dodder is a robber pure and simple, a degenerate outcast from the community of decent plants. From the viewpoint of this chapter, it is possible to believe that the host of the Dodder derives some spiritual or hidden material benefit from the union which makes it distinctly worth while. If such were not the case, it would seem that, through ages of evolutionary development, such plants as Flax would have devised means to escape the Dodder’s clutches.

The Dodder inhabits low ground and pokes an inquiring head above the surface each spring much like any self-sustaining plant. However, it is not long before it attaches itself to some lusty neighbour by root-like suckers, which pierce the stem and extract the nourishing juices. If the supply seems adequate, the Dodder winds its yellow, yarn-like tendrils about the host and allows the roots which connect it to the earth to wither. Its absorbing tubercles look like caterpillar feet; their cells form a perfect graft with the host and gradually disperse through its body. If other plants are near enough, the Devil’s Thread will reach out and tap their food supplies also. A single Dodder has been known to draw nourishment from five or six other plants of different families at the same time, thus indicating that it must have digestive machinery enough to appropriate these varying saps to its own uses. The Dodder has no chlorophyll and therefore no leaves but bears pretty little bell-like flowers which later produce seed.

In the tropical jungles are many parasites of brilliant aspect, which, having no leaves or root hairs, germinate directly on supporting plants and apply suckers to the tissues of their hosts. When seen from the ground, their short stems make them seem all flower, and often very handsome ones. The Rafflesia Arnoldi of Sumatra is a notable example.

Man cannot help condemning such plant practices. Yet all Nature is a struggle for existence. Does it not require some courage and hardihood to come out and do in a bold and open way what the rest of the universe is doing by indirect or underhand methods?

The beautiful Orchids belong to a botanic group of Epiphytes which may be classified as guests or lodgers. Being green, they are able to gather their own living from dust, rain and carbon dioxide in the air. All they ask from their tree-hosts is a branch on which to perch. There are probably few trees which are not delighted to have such delicate, fairy-like creatures add to their own beauty and charm. They wear them much as a woman wears a rose in her hair.

In America there are well-mannered parasites such as the decorative Spanish Moss so common throughout the South. This plant is normal in all respects; except that, perched on a kindly tree, it draws all its nourishment from the air instead of through soil-piercing roots.

The Mistletoe is a perfect example of a mutualist. Early in its aerial life, it sends a root through the bark of its tree companion and during the spring and summer, absorbs much food. When winter days come, and the tree has lost its leaves, the grateful messmate reverses the process and sends into the heart of its friend the larger part of the nourishment which it has been able to store up during the prosperous weeks of summer. The seeds of the Mistletoe are interesting because they are covered with a sticky fluid which enables them to travel from tree to tree on the feet of birds.

That some plants are parasites from necessity or laziness rather than choice is indicated by a Brazilian variety of the Cuckoo-Pint which sits far up on some tree branch and, like an immense spider, sends down to the earth long delicate tubes through which it sometimes sucks food and water.

One of the most interesting facts in plantdom is the alliance maintained by Clovers, Beans, Vetches and other leguminous plants, with Bacteria belonging to the class Pseudomonas. No soil can be fertile unless it contains organic compounds of nitrogen. The earth Bacteria have discovered methods of producing these important substances, possibly extracting nitrogen distributed through the ground. These minute parasites attach themselves to the roots of the larger plants, which promptly enclose them in cysts or nodules where they can lead a sheltered life and manufacture assimilable food compounds for their hosts. When they die, the owners of the roots feed upon their bodies.

What is the art of grafting but a form of artificial parasitism? Very often a branch or cutting is made to form a bodily union with some plant of an entirely dissimilar species. In some cases, the intruder sends roots into the tissue of its host like a true dependent. Grafts of Prickly Pears, Mexican Grapevines and Agaves put forth food-suckers in the soft flesh of the Giant Cactus or the Barrel Cactus much as they would do if planted in the earth. There is here no true diffusive union of partners but mere absorption on the part of the invader.

Even grafting of allied species of Grapes sometimes results in the young plants sending roots through the tissues of the scion, eventually reaching the earth by way of the body of the host. In such cases, the parasite also draws nutriment from its messmate by means of a superior osmotic pressure.

Almost everything lies in the point of view. No man, no animal, no plant is so debased and degraded that it does not radiate some little measure of helpfulness. If “all things work together for good,” even that member of a plant union which seems to act upon that inverted principle of “all coming in and nothing going out” has its legitimate place in the world. As for those numerous examples of share-alike partnerships, they illustrate the principle of the divine law of love which lies back of and above the very real hardships and cruelties of this work-a-day world.

FRIENDLY ALLIES BY THE WATER’S EDGE

CHAPTER V
Allies of the Plant World

“I wish I were a willow tree—
Young wind in the green hair of me
And old brown water round my feet,
And a familiar bird to greet.”

—Elizabeth Fahnestock.

Every division of terrestrial life constitutes a struggle. The plants grow and carry on their business and social activities so unobtrusively that we seldom think of them as appealing to arms—yet their whole existence is a battle royal. They must fight with aspiring neighbours for every inch of their upward growth, and at the same time wage incessant warfare against a hundred insects and animal foes.

Under such strenuous conditions, it is only to be expected that the plants should seek profitable alliances with birds, insects and animals having interests similiar to their own. Such pacts are described by botanists as examples of symbiosis; they most frequently occur between plants and insects, but the plants also have their working agreements with members of the other two great kingdoms of life. In fact, all Nature is a vast system of checks and balances, with every creature preying more or less upon every other creature, except when they can gain more by joining their efforts. Certain Humming-Birds lie in wait near plants which by their nectar-sweets attract swarms of insects, and hard by, Snakes lie in wait for the Birds. The Birds rid the plants of destroying pests; the part of the Snakes in a beneficent scheme of existence is not so apparent, but merely because we cannot see good in a thing is no argument that it does not exist.

Many of the most important alliances of plants are made in response to the law that “Nature abhors perpetual self-fertilization”. This principle is one of the greatest in plantdom; there is a constant necessity for the intercrossing of independent life-streams. The plants go to great lengths to see that the multiplication and evolution of the species is properly carried on.

We always associate Bees and flowers, yet it is probable, that, as a whole, the plants, especially in the tropics, depend more upon Ants than upon any other insects. Many vegetable folk deliberately employ them to keep their leaves and stalks free of obnoxious visitors. The Cow-Horn Orchid, like most plants which perch on trunks and branches, produces pseudo-bulbs into which its vitality can recede in dry seasons. There is always a small opening at the bottom of each of these little tubes, through which Ants enter. They honeycomb the interior with cells and galleries where they can be perfectly dry in the wettest weather. On the approach of Caterpillars, Cockroaches and other Orchid enemies, the residents issue in great swarms to protect their combined host and home.

The species Coryanthes, instead of pseudo-bulbs, grows great masses of fibrous aerial roots among which the Ants dwell. They are ever ready to repel invasions of Cockroaches and other crawlers who seek to eat the tender growing root-tips.

An Epiphyte which is particularly solicitous for the welfare of its insect allies is the Ant-nest Plant, Rubiaceae Myrme. This ingenious creature not only builds nests but builds them made-to-order. Certain enlargements on its stem are hollowed out into chambers with connecting galleries quite ready for their intended tenants. All the Ants have to do is to move in. The kind that usually enter the plant’s service are fierce warriors, Iridiomyrmex Myrmecodiae, with very powerful stings. They form a formidable bodyguard.

Sometimes the Ant warriors of such compacts are quite satisfied to accept the free rental of their snug quarters as sufficient pay and seek their food elsewhere. More frequently, the alliance includes “board and lodging” with the plant issuing wages in the form of nectar, sweet pulp and other food.

The Cherry and Vetch are among plants which secrete a candy-like substance on their stalks which serves as an allurement for Ants to climb and establish their homes there. In many cases, these excretions are also barriers which prevent the Ants from hunting among the plant’s blossoms for honey, as they would thus destroy the precious grains of pollen.

The South American Imba-uba Tree, Cecropia, has a hollow trunk in which Bees and Ants dwell together amicably. The Polygonums Tree of the same continent has so many Ant allies that it is often entirely hollowed out by them. The process often operates so far that men break off the smaller twigs and use them as ready-made pipe stems. The Melastroma Plant of South America provides pouches on each leaf-stalk for the benefit of its black guardian Ants. The Tococas and Mermidones also have Ant-sacs.

In China it is a common practice of the Orange-growers to encourage the visitation of non-vegetarian Ants by placing selected species on trees and connecting the trees by bamboo poles over which the faithful insects can rush their forces to particularly threatened points.

Everyone knows of the large part the industrious Bee plays in the economy of the plant world. Few plants, there are, which are not aided in their love-making by this tiny brown buzzer; some flowers depend upon him entirely in their efforts to propagate the species.

The Bees and their relatives are particularly welcome to the flowers because they do the work of fertilization so well. Wingless insects are undesirable because they offer little guarantee that they will successfully carry pollen to some other flower of the same species. Even if it is not brushed off in the course of their laborious travels, they are not at all particular what kind of flowers they visit and so offer small hope of carrying pollen to its correct destination. Flying insects of the Bee family seem to have the work of cross-fertilization directly assigned to them. On each of their separate, pollen-gathering journeys, they are partial to one particular kind of flower. As they flit from blossom to blossom of the same species, going in and out of flower and flower, rubbing against a group of stamens here and brushing against a pistil there, they fertilize plant after plant in grateful acknowledgment of the store of sweets they are collecting.

Many and ingenious are the methods which flowers adopt to make sure that only invited and useful guests come to their nectar-feasts. The very Ants which guard the lower portions of a plant so well, might become mere greedy plunderers, if allowed to crawl within the flowers. It is not often that they do. Sometimes, the stalks and even the petals of flowers like the Rock-Lichens and the Butter-Wort are coated with some plant chemical exceedingly disagreeable for an insect to crawl over. Various alkaloids, resins and oils in the cell juices also make the flower and its leaves obnoxious to grazing animals. Many plants, like the Mullein and Stinging-Nettle, use bristles and prickles to repel Slugs and Caterpillars.

A common protective device is for a flower to place its nectar at the bottom of a long, narrow tube only accessible to a flying insect having a proboscis. In the Antirrhinum the entrance to the flower is closed to small crawlers by a very heavy corolla. Bees, because of their size and strength, can force their way through. It is said that as soon as the stigma of this flower has been fertilized, the corolla relaxes and Ants and their kind are free to enter and partake of such dainties as are left.

Nettles, Passion-flowers, and Lilies frequently line their interiors with stiff, in-pointing hairs which oppose a most effective palisade against anything that crawls, whereas a flyer provided with a proboscis can stand on the edge and, inserting his straw, drink up the best soda water in plantdom. This existence of proboscides in insects which help to cross-fertilize flowers is the very finest example we have of true mutualism. Here is a case where members of two supposedly different worlds of life have developed highly specialized organs in order that they might help each other.

It is said that Charles Darwin, after noting the extraordinary length of the spur of the Orchid Angraecum Sesquipedale of Madagascar predicted that some day there would be found in that country a moth with a proboscis ten to eleven inches long. Not many years after, Dr. Fritz Müller verified the sagacity of the famous scientist by finding an insect exactly answering this description.

The Birth-Wort (Aristolochia Clematitis) takes no chances with its insect visitors. In entering it, a Bee brushes easily by the down-pointing hairs only to find that, when he attempts to go out again, the bristles present stiff, unyielding obstacles against his egress. In his excitement at this discovery, he buzzes around quite angrily and, without noticing it, thoroughly showers the stigma with pollen and incidentally covers his own body with a good supply to be carried on to the next stop. When this process is quite complete, the flower graciously relents, relaxes its hairs and allows the exasperated insect to escape.

The Pedicularis family uses similiar coercive methods, and by sharp teeth, forces insect-visitors to take a course through the flowers which brings them in contact with both stamens and pistils.

The purple Loosestrife, pretty dweller by banks and meadows, sets a rich table and so always has plenty of insect visitors. It produces six different kinds of yellow and green pollen, and is therefore sure to suit every taste. Incidentally it has two different sets of stamens and stigmas of three different lengths.

Night-blooming flowers only entertain after the sun goes down. All day long they look withered and dead, but with the coming of the stars, they open up to show conspicuous white or light-tinted interiors. A flower like the Silene also exhales a rich, sensuous odor, which, with its light colour, serves to attract such insects as are abroad at night.

Sycamore and Lime trees have humble allies in the tiny mites which live in the retreats built of hairs to be found at the places where the veins of the leaves fork. During the day they hide away from sight, but at night they come out and scour the leaves clean of noxious bacteria and fungus spores.

Pollen of different plants, when examined under the microscope, reveals wonderful facts about the reciprocal relations which exist between plants and insects. Wind-fertilized plants are nearly always without any special beauty of form, colour or scent, while plants which are fertilized by insects are most always conspicuous, brightly coloured and highly scented. In the same way, pollen of the Hazel, Birch, and Balsam Poplar, which is carried by the wind, is small, light, practically spherical and devoid of protuberances. Pollen of the Primrose, Cowslip and Polyanthus, often carried by insects, is deeply furrowed, covered with spines and knobs, strung together by sticky threads and, in other ways, provided with apparatus which enables it to adhere to any object which it touches.

The pollen of the Hollyhock and the Dandelion consists of large, beautiful, spherical grains covered with spikes. The Rhododendrons, Azalias, and Fuchsias produce great masses of grains bound together by viscid threads. Many of these bits of life-principle are geometric masterpieces. A pollen grain of the Cobaea Scandens is one of the most fascinating objects of the microscopic world. It is perfectly spherical and cut into small hexagonal facets like the eyes of a fly. Grains of pollen of all kinds vary between one two-thousandth and one two-hundredth of an inch in diameter.

Alliances between plants and birds are more important than we imagine. The tropical Humming-birds and the eastern Sun-birds are in habits exactly like the pollen-carrying insects. To watch one of these brilliantly coloured creatures hovering over a flower or flying directly into a blossom after nectar, is to almost always mistake it for a Butterfly.

Many birds are invaluable allies of the plant world. They devour thousands of leaf-eating insects per day and so keep down the army of enemies which would otherwise destroy whole forests. Birds like the Woodpeckers rid tree bark of wood-boring crawlers.

In the human world every partner does not always live up to his agreements. And there are evidences that both plants and their allies sometimes engage in questionable practices, bordering on deception and chicanery.

The insects are often enough the offenders, and their crime is most frequently one of robbery. If they can get the sweets they are after without carrying out their share of the bargain, they will do so. Bumble Bees have been observed to cut through the flower-walls of a Nasturtium and so extract its nectar without coming near the pollen-producing stamens. Sweet Peas frequently ignore the insects and fertilize themselves. The Hawkweed (Hieracium) has so little faith in insect allies that it produces seeds parthenogenetically, that is, without the union of sex elements.

Alliances which start out advantageously for both parties sometimes degenerate into mere sinecures for one or the other. The naturalists Ihering, Ule and Fiebrig, working in South America, a few years ago concluded that the association of the plant Cecropia and the Aztecan Ants, long regarded as a classic example of mutualism, is by far of greater benefit to the Ants. The openings which the Ants make into the hollow interiors of this plant also allow the entrance of certain destructive insects, and the Ants themselves attract Woodpeckers which damage the plants. It is also alleged that these same Ants, and the ones which inhabit the Humboldtia Laurifolia, are often so busy feasting on nectar that they do not stop to repel invasions of foliage-destroying insects.

While man is the greatest enemy of the plant world, he is also at times its greatest friend. When it is to his advantage or when he is prompted by a sincere love of Nature, he becomes a strong and helpful ally. He aids his fellow creatures of the vegetable world when they are sick or injured and, by improving their environment and protecting them from attack and danger, enables them to develop to best advantage. A wizard like Luther Burbank helps them in their efforts at race improvement and development.

In Egypt and Arabia, man has acted as carrier of pollen for centuries, and has thus insured an abundant Date crop. The same thing is often done in other parts of the world with Apples, Pistachios, Melons, Cucumbers and other plants having unisexual flowers.

CHAPTER VI
Marriage Customs of Plants

“Pale primroses
That die unmarried.”—Shakespeare

“Love consumes the plants” once wrote Linnaeus, and the observation of every student of Nature goes to confirm his statement. The plants marry and are given in marriage. Reproduction is undoubtedly their chief end in life.

The simplest and most primitive plants have no sex but produce new individuals by splitting their single cells in two. It is in the thread-like bodies of Pond Weeds that we find the first beginnings of the principle of generation by union. These lowly creatures consist of single cells strung end to end like beads in a necklace. When two of the living chains happen to find themselves parallel to each other, certain of the cells reach out and join those opposite them to form new cells. Such a mixture of life forces is always beneficial to the race.

In the higher plants the same process is carried out in a little more elaborate way. Of the two cells which unite, one is small and active, and is called the male or pollen cell. The other is larger, richer and more passive, and is the ovule or female cell.

It is one of the main objects of each plant’s life to see that its ovules are fertilized by pollen grains from some other member of the same species. When this is impossible, flowers are reduced to fertilizing themselves, but if this continues very long, degeneracy is very apt to result. It is not wise to marry one’s first cousin.

Many plants depend upon the wind to distribute their pollen. Such species bear slight, inconspicuous flowers which not infrequently cluster together in long, pendent catkins. This was undoubtedly the first and original form of plant marriage. Though often successful, it is very wasteful and undependable. “The wind bloweth where it listeth” and loses a million grains of pollen for every one it lodges.

One hazy day in the long ago, some plant had a brilliant idea. “There are a number of insects which are in the habit of paying me unwelcome visits for the purpose of eating pollen. Why can’t I make use of these thieves and turn their marauding habits to my own advantage?”

No sooner said than done, though it doubtless took many centuries to get the plan in thorough working order. It was a new departure in the plant world and led to various revolutionary changes. In all probability, there were no bright-hued flowers before the advent of pollen-eating insects. In the beginning, at least, flowers were developed as the signs by which plants advertised their wares. “We will make ourselves luringly attractive,” reasoned the plants. “We will add to our bright-coloured petals the sweet delights of nectar and honey. While the insect is eating at our table, we will shower his back with pollen and, going forth to some floral neighbour, he will unwittingly become the marriage priest of our race.”

This was the idea, and in many diverse and wonderful ways the plants have carried it out. The first flowers were developed by training certain stamens to flatten and expand themselves, daub their surfaces with colour, and so become petals. This evolutionary fact can be seen today in the white Water Lily, where concentric rows of stamens gradually merge into petals. Double Roses and Poppies are examples of the same thing.

The formation of flowers was only the first step. It is not enough to get the insect to come to the plant. Once he is there, means must be found to make sure that he performs the marriage duties assigned to him. Each flower takes care of this problem in a different way.

At ordinary times, the Gorse is a closed flower, provided, however, with a little step or platform on which a Bee can alight. As soon as an industrious honey-seeker has settled down on this little floral porch, his pressure causes the entire corolla of the flower to spring violently open and shower him with pollen. A Gorse flower which has thus unburdened itself at once hangs down dejectedly and is no longer the object of insect regard. The Lupine and the English Bird’s-Foot Trefoil entertain their tiny visitors in a similiar way.

There are two different arrangements of sexual organs in the Primrose. One variety is provided with long stamens and a short pistil. The other has the reverse combination of short stamens and a long pistil. In both cases, the nectar is in a pit at the bottom of the flower. As long as an insect visits short-stamened flowers, he collects pollen on the upper part of his proboscis. Happening to enter a short-pistiled flower, this portion of his drinking tube is now opposite the female organ and fertilizes it. In the same way, the insect’s feet gather pollen from the long-stamened flowers and deposit it in the long-pistiled variety. By such involved methods does this particular flower make sure of fertilization.

Sage flowers have only two stamens but they do the work of forty. Using their power of movement, they bend forward and deliberately embrace a bee as soon as he enters their chamber. They do not release him until he is covered with their yellow pollen.

The English Figwort has adopted repulsive methods of entertainment. It has contrived to make itself look like and give forth the odour of decaying meat, because it knows that it will thereby attract certain Wasps. The South African Stapelia does the same thing with the idea of alluring Carrion Flies. Still another imitator of similiar kind is the pale-green Carrion Flower whose visitor is the Blow Fly.

When in repose, the stamens of the pink-white Mountain Laurel (Kalmia Latifolia) curve so that their anthers or pollen-bags fit into corresponding pits or depressions in the petals. When a Bumble Bee happens along and blunders among these delicate organs, the stamens spring up and shower his back with pollen.

Everyone is familiar with the purple barber pole of the Cuckoo Pint which stands up straight out of a pulpit-shaped leaf. This barber pole is the upper end of a fertilizing device of marvelous efficiency.

Down in the shelter of the cup-shaped leaf, the pole is covered with primitive male flowers, without petals or without sepals, in fact, nothing more than simple stamens. Below them are rudimentary female flowers consisting of unadorned pistils. Certain Midges and Flies are attracted into the leaf cavity of the plant by the store of sweets at its bottom. Traveling down the pole, these would-be feasters readily pass the guardian hairs just above the stamens, pass the stamens themselves and unintentionally fertilize the pistils with pollen they have picked up on other marauding expeditions. Having partaken of honey, the Flies seek to escape, but now find the way barred by the down-pointing hairs which have bristled up in a militant manner. The insects must stay until the plant decides to release them, which is never until the stamens have ripened and showered them with a fresh supply of pollen.

The Orchids are among the most beautiful and extraordinary flowers in the world. Their noteworthy development has come about through their efforts to secure abundant and efficient insect fertilization. So certain are their methods that they ordinarily do not require the services of more than one stamen.

In one variety, the English Spotted Orchid, the pollen is enclosed in two sacks or bags provided with long stems. These sacs are lodged in special cavities near the pistil in such a manner that the sticky ends of the stems come in contact with the head of a nectar-sucking Bee. They adhere firmly. When he departs he has two bulbous ornaments for a crest. At first they stand erect, but as he flies, the air dries them and they incline forward on curved stems. When he is ready for his next cup of honey, they are hanging down in front of his eyes like a new kind of pawnbroker’s sign. It is no mere happenstance that in this new position the pollen sacs are deposited on the stigma of the second flower’s pistil. By such ingenious marriage customs, the Orchids have become a dominant family in plantdom. They are in the ascendency even in the tropics, where their frail bodies have to compete with hosts of plants which are physically much more vigorous.

Between the Yucca and the Yucca Moth exists a wonderful life-long partnership for the purpose of furthering the reproductive processes of both. Surely, Nature moves in mysterious ways.

Insects are the chief marriage priests of the plant world, but in the tropics they are aided and abetted by Humming-Birds, Sun-Birds and Lories, which are all provided with long, tubular tongues.

Most insects act as if they were unaware of the important place they occupy in plant hymeneals. So intent are they on their honey-gathering that they become covered from head to foot with pollen without appearing to notice it. Yet in a few instances, the Bees not only recognize that they have been pressed into the plant’s messenger service, but by underhand methods seek the rewards of labour without giving adequate return. They have learned how to cut a hole in the calyx tube of the Bean and the Scarlet Runner, and get at the precious honey by short cut. If all Bees and other fertilizing insects should master this trick, the flowers would have to wear defensive armour or perish.

Pollen to be effective must remain dry. The plants have perfected many devices to shield it from moisture. Frequently, the flowers hang so that their petals act as tiny umbrellas for it. Others wear rainy day hoods, and practically all close when the night mists are abroad.

The necessity for dry pollen obtains even among the water plants. If they are surface-floaters like the Pond Lily or the Victoria Regia, it is easy enough for them to thrust their blossoms up into the air, where they may be as dry as though they were on land. The sub-aqueous plants have a harder problem and are sometimes driven to developing their flowers in leaf air-chambers below the surface. The Water Chestnut (Trapa Natans) makes itself buoyant at its flowering period with generated air and rises en masse to the surface. After fertilization, it sinks again to its sub-aqueous quiet.

Self-fertilization in its strictest sense occurs within the individual flower. Plants only resort to it as an extreme measure and commonly make use of many devices to prevent it. In the Iris, the petal-like stamens are in direct contact with the pistil and yet self-fertilization does not result, because the pollen surface is always carefully turned away from the ovary.

By bringing their pistils and stamens to maturity at different times, many flowers make sure that they will not fertilize themselves. Such is the case in the Bulbous Buttercup and the Arrowhead.

Flowers of the same tree or bush might be called distant cousins. Their union results in healthy offspring, though the marriage of still more divergent individuals is preferable. Plants like the Begonia, which bear single-sex flowers, often grow in somewhat isolated positions and so must intermarry a great deal among themselves. Staminate flowers at the top of a stalk can shower pollen over many female flowers growing below them.

The exception always proves the rule, which explains why we find a few flowers which deliberately choose to fertilize themselves. In the Fuchsia, the flower droops, throwing the long pistil below the stamens, which can readily drop pollen onto it. Minute hooks hold the petals of the Indigo and Lucerne partly closed until the flower is completely developed. When they give way, the petals fly back, so shaking the whole flower that the anthers shower pollen on the pistil. The single-sex flowers of the Aloe bend near each other at mating time.

The Violets and Polygalas are also largely self-fertilizing. They are, therefore, borne under the leaves or close to the ground, where they attract little attention.

The love and marriages in plantdom may seem to be largely instinctive and mechanical, but that is probably because we have not investigated them sufficiently. The Persian poet Osmai believed that the plants had affairs of the heart as real as those recorded in the human world. Here is his account of one:—

“I was possessor of a garden in which was a Palm Tree, which had every year produced abundance of fruit; but two seasons having passed away without its affording any, I sent for a person well acquainted with the culture of Palm Trees, to discover for me the cause of the failure.

“‘An unhappy attachment,’ observed the man, after a moment’s inspection, ‘is the sole cause why this Palm Tree produces no fruit.’

“He then climbed up the trunk, and looking around, discovered another Palm at no great distance, which he recognized as the object of my unhappy tree’s affection; and he advised me to procure some of the powder from its blossoms and to scatter it over the branches. This I did; and the consequence was my Date Palm, whom unrequited love had kept barren, bore me an abundant harvest.”

FLORAL OFFERINGS IN A MOUNTAIN CATHEDRAL

CHAPTER VII
Art in the Plant World

“As if the rainbows of the fresh mild spring
Had blossomed where they fell.”

The plants are perfect artists. From the budding of the Rose to the sudden shooting forth of the seeds of the Wistaria, everything they do is in perfect taste. Ugly flowers are decidedly uncommon. Those which human judgment declares to be less lovely than their fellows have their attractive points, if we take the trouble to look for them. If art is a desire for beauty, a searching after perfect harmony, then the plants and flowers are the most artistic creatures in the universe.

Plant colours are particularly interesting. The flowers are master-craftsmen when it comes to the adornment of dainty, delicate petals with pigments which are the distilled essence of a thousand rainbows. No other quality in the natural world gives man a deeper emotional enjoyment. Floral colours speak a whole language of their own of which we can get only faint interpretations.

Cold biologists explain that the beautiful hues and shades of plantdom are largely designed to attract insects and so secure a necessary distribution of pollen. There is no doubt that this is true, but for one to believe that this is the sole function of a flower’s beauty is to reduce the world to a materialistic basis and banish all thoughts of the esthetic, the spiritual and the ideal. The flowers are permitted to adorn themselves in bright raiment at least partly in order to satisfy the universal craving for the delicate and the artistic.

It should not be imagined that the gayest and most brilliantly coloured members of the plant world are always residents of the tropics. The hot countries undoubtedly produce many specimens of startling hue and pattern, but it is often their ostentation and exotic character, rather than their beauty or charm, which attract attention. They are apt to be a bit barbaric and not as numerous as they are reputed to be. For great masses of beautiful flowers, we do not go to Mid-Africa or Cuba, but to the mountain-bound meadows of the Alps, the plains of Australia, or the prairies of America. What is more startlingly beautiful than a field of Yellow Buttercups or Black-eyed Susans which can be seen anywhere in the eastern United States? Where can our eyes feast upon a more wonderful scene than a field of Wild Verbenas and Delphiniums as found in Texas? In the tropics the flower masses are more scattered. Even the far-famed Orchids are only abundant in occasional favoured spots.

The gardens of our large country estates offer floral displays which cannot be rivaled anywhere. Our temperate zone Roses, Peonies, Hollyhocks, Wistaria, Lilacs, Lilies, Tulips, Hyacinths, Gentians, Asters, Anemonies and Poppies are the most delicate colour creations in existence. For brilliance and alluring charm nothing surpasses the Mountain Laurel and Rhododendrons of the East, or the Trumpet Vine and Yellow Jessamine of the South. The gorgeous Azalias, Camellias, Pelargoniums, Calceolarias and Cinerarias also belong to the regions which have cold periods in their annual weather schemes. Even the humble Gorse is clothed in gold, while the prickly and much-despised Cactus bears little crimson-coloured bells.

It is quite evident that man got his original idea of colour from Nature, particularly the plant world. Why is it that we are inclined to wear green in spring, brown in autumn, and all manner of colours in summer? Simply because, consciously or unconsciously, we are imitating Nature. We take pigments and dyes and get a pale similitude of an exquisite flower. If it happens to be a Rose, we name the colour after it. Sometimes we name tints after the sky or an animal or a bird, but in these cases, we might just as well have gone to the flowers for our nomenclature.

Every tint and hue which we can ever hope to reproduce is present in the plant world. The flowers by no means monopolize them. On close examination, a single stalk and leaf exhibit a wonderful variety of colour. In the Begonia and the Sea Holly, the stalks are exactly the same colours as the flowers. The wild Cranesbill sports a crimson stem. The stalks of Poplar leaves are a vivid yellow. To speak of “green leaves” is to speak in the most general of terms. What is more exquisite than the silver gray to be seen on the backs of many tree-leaves, notably the Alders, Willows, and Poplars? Many leaves join the Wild Lettuce in having purple backs. The reverse sides of Magnolias and Rhododendrons are red-brown. In the autumn, nearly all leaves show brilliant patches of colour.

In borrowing Nature’s colours to set forth our ideas, we have become possessors of a mighty vehicle of expression. With yellow, we can speak of life, light, cheer and vitality. Red tells of fire, heat, blood, excitement and passion. Blue indicates coolness, quiet and restraint. In choosing green for its most universal colour, Nature harmonizes life and restraint, warmth and coolness, as represented by the component blue and yellow. In the same way, when she wants to concentrate the maximum colour power in a single fruit or flower, she uses orange, a combination of light and heat, vitality and excitement. Purple represents a neutralized idea. Red vitality is tempered with blue restraint, which results in mysticism. Nature clothes the Poppy in red to suggest power and strength. The royal purple of the Aster and the Violet is purposely calculated to arouse a feeling of mystery and awe.

Our man-made cloth designs often show various plant forms intact in the weave. The same is true of lace, while one has only to look at the miniature flower gardens which women wear on their heads to realize the potent influence of plants in the domains of millinery. An important plant element seems to run through many fields of applied art.

In some ways, the beauties of form and structure are more appealing than chromatic charms. Lines are more refined and fundamental than colours. A feathery mass of tree-twigs seen against a distant horizon is exquisitely beautiful. A symmetrically shaped tree comes very close to presenting an idea of pure form. One may argue that it is impossible to dissociate all idea of colour from a natural object. This is theoretically true, but practically, while we are impressed by the colour of the Rose, it is the structural beauty of the Palm and Weeping Willow which attracts our eye.

Nature is the true and original sculptor. From her we learn our rules of symmetry and design. All her plant creations are finished with a faithfulness to artistic principles which is quite exact. Nor does she build houses with false exteriors. Her structures show forth the necessity of truth in real esthetic creation. Bartholdi’s exquisite Statue of Liberty, viewed from the interior, is an ugly, hollow tube. A stalk of corn not only has a pleasing exterior but is made up of symmetrically formed and packed interior cells. From a giant Redwood to a microscopic vegetable organism, every line and structural unit in the plant world is perfect in its inception and execution.

Each plant, viewed as a whole, has its own peculiar style of structural beauty—the variation of line and form which stamps it with charm. This differentiation extends to all parts of the plant and gives character to leaves, stem, flowers and fruit. Marvellous is the art worked out in the minute parts. The tendril of the Passion Flower, the radicle of a Seedling Maple, the feathery hair on a stalk of Mullein—all these are shaped according to the unknown law of beauty. Probably every geometrical form exists in some seed pod or fruit. The artistic little seeds of the Milkweed and the Dandelion are packed into their containers with a skill which cannot be duplicated, once they are dislodged. There are a million seeds in the capsules of certain Orchids. Many seed vessels are tipped, balled, carved and frescoed.

The same delicate touch is seen down to the last cell. Plant stems range from the common tubular variety to four-sided, hexagonal and octagonal forms. Trees exhibit exquisite mosaics in their rough bark. Bell-shaped flowers and flowers which are tubes, rings, ovals, trumpets, horns, and cones are only some of the pleasing shapes to be found in this part of vegetable anatomy.

It is a significant thing that there are few straight lines in plantdom. Everything is built in fascinating and alluring curves. There is a definite idea of symmetry to be observed everywhere. The beautiful, five-pointed, leaves of the Sweet Gum Tree are arranged so that each one fits into an interstice between two others and so obtains a maximum supply of air and light. In general, leaves nearest the ground are largest, thus insuring each its supply of sunshine.

When we study ornamental design, ancient and modern, we see plant forms on all hands. The Greeks and the Moors were the only nations to be content with geometric shapes and lines—and they were only content at times. All other peoples have given plants and flowers a large place in their decorative conceptions. The Egyptians and the Assyrians, who may be considered the first civilized artists, used the Palm, Papyrus, Lotus and Lily. The Greeks and Romans were partial to the Acanthus, Olive, Ivy, Vine, Fir and Oak. The Gothic art of Germany, France and Spain featured the Lily, Rose, Pomegranate, Oak, Maple, Iris, Buttercup, Passion Flower and Trefoil. The modern Chinese are more conservative and seek inspiration only from the Aster and the Peony. The Japanese use the Almond, Cherry, Wistaria and the graceful Bamboo in their art work. These various plant forms are sometimes quite conventionalized but are readily recognizable, whether they occur in architecture, carvings, paintings, illuminations, tapestries or cloth fabrics.

The plant world has been man’s most constant and readily apprehended artistic model. Yet when we see the multitude of attractive lines, curves and shapes in Nature’s great garden, we wonder that he has so limited his imitation. One rarely sees the Thorn-Apple, the Hawthorn, the Daisy or the Tulip in wood or stone, yet they are all exquisitely beautiful.

Again, artists and artisans throughout the centuries have nearly always confined themselves to but two phases of plant life—the leaves and the matured fruit. Tendrils have been neglected or treated with characterless mediocrity. Thorns, leaf stipules, buds, pods, and leaf scars have been universally overlooked. Who has ever seen the fruit of the Rose in ornamental art? Why is it no one has thought to use the leaf scars of trees like the Horse Chestnut as decorative units?

Grapes and Pomegranates are reproduced with some justice, but the various small berries almost always appear as miscellaneous spherical bodies, whereas they are really greatly varied. The Snowberry, Privet, Laurel and Barberry have distinct characteristics of form and shape.

There are chances for worlds of artistic expression in various seed pods and fruit vessels. An open Pea Pod occurs in certain Renaissance ornament. Why not (and this is not intended to be humorous) a String Bean?

Even a lowly thing like the scarred stalk of an old Cabbage has a pattern worthy of imitation. The shields or remains of leaves of former seasons form an artistic detail of the growing Palm Tree. The Romans occasionally reproduced them on their columns. Leaf shields are also met with in Greek border ornament.

Why must our sculptors represent the various fruits as bursting with mature mellowness? In many cases, the unripe fruit is artistically more attractive than when in the later stages of development.

We rarely think of disease or decay as being pleasing, yet some plants are artistic even in their dissolution. Certain galls and cankers draw beautiful designs on the bodies of their victims.

Everything in plantdom has its own peculiar style of structure and beauty. All are worthy of imitation and reproduction, provided only it is done in the right place and the right way. It must be remembered that, in origin, ornament was first symbolic and then decorative. Real ornament is never unduly prominent but subordinates itself to the idea and structure of the whole.

Man has imitated the plants also in things of a lowlier nature. Cups, vases, pitchers and other utensils were undoubtedly first suggested by similar shapes in plantdom. It is not too fantastic to imagine that the smoking pipe is modelled after the flower known as the Dutchman’s Pipe. An electric wire running down the chain of a suspended lighting fixture looks all the world like a climbing vine. Human jewelry has its prototype among the flowers. Our garden beauties powdered their faces long before their human sisters ever thought of that method of self-adornment. It is said that Greek dancers and athletes sometimes exercised before certain slender plants in order to pattern their bodies after them.

We are not all artists or interior decorators, and yet we can all make use of the artistic possibilities present and inherent in our plant friends. We can cultivate and further the use of plants and flowers in and about our homes. Europe is far ahead of us in this respect. In England, a city house may be ever so frowsy and run-down but it will be sure to have its well-kept window boxes. The suburban homes of labourers and other lowly folk are often veritable bowers of loveliness. The German must have a garden in which to drink his beer. If there is none handy, he builds one, and cool and delightful he makes it. In many European cities, all the houses come out to the building line and even arch the sidewalks. Not a bit of greensward is in sight. Yet shrubs, flowers and vines spring from every sill and balcony and so make the streets to blossom as the Rose.

American cities are too inclined to be barren wastes of brick and stone, with but scant provision for plant beauty. Even the rich, who have their elaborate and beautiful country gardens, seem to forget the plants and flowers when they come to the city. The self-tending Ampelopsis and Wistaria vines are the only plants at all common. Our short summer season and the fact that so many people do not occupy their city homes in warm weather are a little discouraging, but need not shake the enthusiasm of any one really interested in plants. For a few dollars a season florists will assume all care of exterior plants and vines.

The man who has a little plot of ground before his door is indeed fortunate. Even a well-clipped grass lawn is a refreshing asset. Sweet Peas train well against a wall. Pansies flourish in shady spots and Nasturtiums wax beautiful where other plants fail.

A brown stone front, flushed to the sidewalk in the middle of a block, need not go without floral decoration. Even a terra cotta box on either side of the entrance is capable of holding much growing joy. Evergreen shrubs fit well into such surroundings. A window box has great possibilities. In early spring, Crocus, Narcissus and Hyacinth flourish in it to advantage. Ivy-Geraniums of smooth waxy leaves and graceful loose sprays will grow all summer. Vines of various kinds can be trained so as to make very effective window screens.

The subject of home plants is fascinating. It is well to note that it is not always necessary to go in for the more elaborate varieties. It is surprising what a delicate and pleasing decoration is made by so humble a thing as a sprouting Carrot or a Sweet Potato Vine.

Outdoor and landscape gardening are whole sciences unto themselves. In general, a Renaissance house looks best surrounded by formal and well-clipt flower beds. Houses on the Gothic order should have undulating lawns and irregular groups of shrubs and trees about them.

Plants and flowers are the first and original artists. Their creations are our best and most worthy models. We can use them both as examples to be imitated and beautiful objects with which to surround ourselves. They are one of our greatest esthetic inspirations.

CHAPTER VIII
Music in the Plant World

“Many voices there are in Nature’s choir, and none but were good to hear
Had we mastered the laws of their music well, and could read their meaning clear;
But we who can feel at Nature’s touch, cannot think as yet with her thought;
And I only know that the sough of the pines with a spell of its own is fraught.”

Music is a language—a species of soft, dreamy speech which makes up for its lack of definiteness and precision by a beauty and harmony which can best be described as divine. Indeed, the ancient Greeks made music an all-inclusive term for the higher conceptions of life. Dancing, poetry, and even science were supposed to be under its sway, while the revolution of the heavenly bodies created that “music of the spheres” which entertained the gods.

It would be better for mankind if this sentiment were more popular today. It is a narrow notion which confines the idea of musical harmony to the sounds produced by certain man-made instruments. Art which is restricted to workings in oil may be very pleasing but it is also very much limited. Music which is only interpreted on a violin or a piano falls far short of its grandest possibilities. To certain minds, the sighing of the wind through a Pine forest is more exquisitely expressive than a hundred breath-blown symphonies. When men cannot agree as to what is music among the sounds produced by their self-created instruments, dare they lightly ignore the many pleasing sounds which accompany the operations of Nature?

To an American ear, Chinese singing sounds like squealing and a Fiji concert like a vociferous boiler factory. Yet a Chinaman or a Fiji Islander will leave our grandest operatic efforts in disgust, though he may be pleased with the preceding orchestral tunings. Where are we to set the standard? Is it not safest to fall back on Nature for our truest conceptions?

The real sublimity of Nature lies in her vocalism. A soundless world would be greatly lacking in charm. The endearing noises of the woods and the fields often become so familiar that we fail to notice their individual merits. Yet they are there. Their sudden cessation would leave a terrible and unbearable gap. The woods are filled with gaily costumed feathered minstrels. The meadows are great emerald stages of song and fancy. The very grass roots are filled with little insect-fiddlers who chirp cheerfulness. Wind, water and rain all furnish a grand and beautiful accompaniment.

Nature sings in the inharmonic scale, that is, a scale which takes in all intervals. Between the piano notes “C” and “D” lies a great space. They only represent halting points in the ascent of sound. Just as in the spectrum there are a hundred variations of shade between blue and green, so the cultivated human voice can hint at a hundred intervals between “C” and “D”. Nature uses all the tiny shades of sound there are, and certain humans have followed suit. To the Arabians, water “lisps in a murmuring scale.”

Occasionally, Nature uses the diatonic scale familiar to our western civilization. When the wind unites its vibrations into the long shrill note we call the whistle, it is playing according to our musical rules. Water, when falling perpendicularly from a great height also gives forth a long, steady note. Even the rhythmical quality so essential to good music is not lacking in such phenomena as rain pattering on dry leaves. This sound has proved unusually appealing to many people. The Mexicans sometimes attempt to imitate it by means of clay rattles.

Not only does the countryside continually sing a great symphony, but each region has its own acoustic properties. While large cities maintain a discordant and incessant roar, the country is filled with soft and pleasing voices. Birds, animals, water and wind give forth quaint musings of the most soothing nature. Once in a while the woods go on a musical jag and every instrument becomes discordant. Under the influence of the bright moonlight, the inhabitants of the South American jungles sometimes seem to go mad. The hoarse roars of the Tiger mingle with the piercing shrieks of Parrots and the shrill wailings of Monkeys, while the croaking of Bull Frogs and the dismal hoot of Owls is deafening. Jaguars scream as they chase Monkeys through the tree-tops.

The various members of the plant kingdom are the principal instruments upon which the wind plays. Without the obstruction offered by plants, trees, rocks, and houses, we should not hear the wind at all. The trees, because of their size and exposed positions, are most noted as plant-musicians, but the grasses and herbs are also very susceptible to the caressings of the wind.

Who has not heard and gloried in the music of the Pines? The sharp needles of these big conifers seem unusually fitted for esthetic expression. They are the Aeolian harps of the woods. During a storm, they sing in a mighty chorus of acclaim. At such a time, the breaking of many small branches sounds like the snapping of overstrained violin strings.

Almost any tree located on a cliff or on the edge of a mountain, becomes a musician of the first order. It is apt to take on the sorrowful tendencies of solitude. The weepings, wailings, murmurings, groanings, sighs and whispers of the universe vibrate through its branches. It would seem as if such a tree were trying to express many mysterious wonders of which man has little knowledge.

The trees are not altogether dependent upon their leaves for their music. The barren branches of fall and winter sing in a most attractive way. Their dry and discarded leaves litter the ground and carry on crackly songs of their own, or sing as they play tag in whirls of wind. The Elm is a pleasing autumn singer and the Willows, when covered with ice, rattle their twigs like a minstrel’s bones. As the winter wind hums around the Cottonwood Trees, it rocks the seed balls in their natural cradles with a sighing, crooning sound. This is the way the Tree sings to her babies! When the wind soughs through a hollow tree, it produces a ghostly sound suggestive of a mourning or dying person. A current of air rubbing two boughs together causes a scrunching sound which sends the shivers up one’s back.

It is reasonable to believe that every tree and plant has its own individual voice as set in motion by the wind. A Nature-lover does not have much difficulty in distinguishing a great many. The desert Sage whistles in the wind; the Cedar laughs in the storm; the air rustles through a Wheat field; an agitated Sugar Cane or Corn field gives forth a sound like tinkling glass. The noise produced by a high wind in the Southern Smilax has been likened to a harp struck at random.

The bursting pods of the Witch Hazel pop gently and the seeds fall among the dead leaves like so many buck shot; the Oxalis sends forth its seed-babies with the crack of a pistol shot. Members of the Bean family moan in the breeze like plaintive violins. The Squirting Cucumber gurgles not unlike certain frogs. The Sunflower is a professional drummer who rattles his seeds about in his pods. The Rattlesnake Iris holds its seed-capsule in such a way that it gives an excellent imitation of the warning noise of the reptile for which it is named. Catalpa pods snap like horse-whips, but Cat-Tails sigh like small reed instruments.

Early man gained more inspiration and pleasure from the music of the plants than his wiser but more worldly successors. It is said that the idea for the first flute was obtained by listening to the wind sigh through the Reeds on the shore of a lake. The first stringed instrument was probably a fibre accidentally stretched across a hollow shell. The classic Aeolian harp consisted of a wooden frame containing a thin sounding-board over which were stretched a number of strips of cat-gut. If placed before a half-open window so that an air current strikes it sideways, it gives forth a great volume of harmonious notes in several octaves. This is a clear case of catching the music of the wind. In a cruder, less harmonious way, the Japanese glass tinklers of our day do the same thing. The humming of telegraph wires and the strange chirping of a wireless instrument are also a kind of singing.

All the plants are not expert musicians, which explains why they often seek to make up for their own deficiencies by hiring numerous birds and insects to make melody for them. These musicians are employed in the truest sense of the word and receive their pay in food, shelter and protection. In the air and on the ground, by day and by night, they sing and fiddle for their hosts. The broad leaves of the Water Lily (Victoria Regia) are veritable music schools of Frog practice. Every voice from croaking bass to youthful tenor is heard! Every tree has its Frogs and Birds—every bush and shrub innumerable insect warblers.

The birds are the plants’ vocalists. Their songs and delightful twitterings are among the most familiar things in Nature. The music of the large body of insect-instrumentalists is carried on in such obscure places, and often so far down among the very roots of the plants, that a considerable investigation of their methods may not be amiss. They are especially active after sundown.

The common Grasshoppers form a great corps of violinists. A large vein on the inside of their thighs makes an ideal bow. It is roughened not with resin but by a hundred minute spines. When this vein is rubbed to and fro on the serrated veins of the insect’s wing-cover, a shrill tone is produced. Sitting on its haunches, the Grasshopper saws away with both hind legs at a great rate. The interesting discovery has been made that the velocity of the strokes increases with the temperature. Grasshoppers in large swarms emit a low roar.

The Locust is a near relative of the Grasshopper. His music is produced by scraping one wing across the other. The Cricket uses the same method. When he is a house species, he fiddles in a higher tone. The gold-green Muskback Beetle is an exquisite violinist. His instrumental methods are most peculiar. His sharp breast acts as a bow which he draws across a small group of veins on his wing covers. The resulting music is so faint as to be almost inaudible.

To Bees, Wasps, Hornets, Flies and Mosquitoes we may ascribe reed instruments. They depend upon the rapid vibration of their tiny wings to get their effects. The respiration openings distributed over the body of a Bee, by giving resonance to the tone, aid in the process and turn the whole insect’s body into a small clarionet. The drowsy buzz of the honey-gatherer is only attained by swinging its wings at the rate of four hundred vibrations a minute. People who have good ears for music have observed that the ordinary Bee drones his song out on G sharp. The House-Fly is credited with singing at F with a preliminary grace note on E. Everyone is familiar with the high thin plaint of the Mosquito.

There are many drummers in the insect orchestra. The Cicada operates a small kettle drum. On the front of its body, a tough membrane is stretched over a small cavity. When set in motion by a special muscle, it gives out a surprisingly agreeable sound. The Greeks enjoyed this music so well that they often caged the Cicada much as they would a bird. In the hatching time of the seventeen-year variety, the energetic drumming of thousands of the insects rises into a scream which is far from melodious. Under such conditions, the noise can be heard for half a mile. Travelers tell of a giant South American species which produces a drumming which is as loud as a locomotive whistle. An uncanny drummer is the “Death Watch Beetle.” It uses its head for drumsticks and when in the wood of furniture often plays a tattoo with considerable skill. Superstitious people, for no apparent good reason, sometimes insist this is a warning of impending death. Even the pretty little Butterfly on occasion is a drummer. With hooks on its wings, it makes a sharp crackle, not unlike one of the weird noises sometimes used by human “traps.” Beetles play the bones.

The Bamboo Tree is sometimes the possessor of a whole corps of intelligent and efficient drummers. They attach themselves to the under side of the leaves, from which vantage-point they strike them with their heads whenever their services are required. An Ant of the Sumatran species keeps wonderful time. Though spread out over a number of square yards of leaf space, a group of these tiny creatures will start and stop tapping at the same instant.

Perhaps in some far-distant age, mankind will begin remotely to understand the significance of the music of the plant world and its allies. We have no right to say that the plants are not true musicians. While we may only understand their system of harmony in part, we can realize it contains hidden beauties just as the presence of microscopic organisms in the world is indicated by their effects rather than by actual perception.

CHAPTER IX
Science in the Plant World

“Weak with nice sense, the chaste Mimosa stands,
From each rude touch withdraws her timid hands.”

Plants are profound scientists. Their knowledge may not be as broad and far-reaching as that of man, but they are more successful workers than he. With all his wonderful discoveries in physics and chemistry, man as a class has not yet learned to conduct his own body so as to make it yield the highest efficiency. In fact, members of the human race are today wearing out their frames at a faster rate than ever before. Adept at running huge mechanisms of steel, they are neglectful of those most delicate and wonderful machines which are bound up with their own life processes.

Plants are not so prodigal. Whenever they are given a chance, they develop and expand their powers in the most marvelous way. They bring out the latent strength in their beings and so conduct themselves as to conserve their energies. Whether by instinct, reason or blind force they always know just what to do and how to make the most of their heredity and environment. Their efficiency rating is one hundred per cent.

As the whole life of all plants is a scientific progression, we can only consider in the brief limits of this chapter some of the more startling instances of the marvelous sense they exhibit in dealing with Nature’s forces.

Probably one of the reasons we do not always think of plants in the human, sympathetic way we should, is that we are inclined to regard them as quiet, static objects, playthings of every wind that blows upon them. Such is far from the case. Life is motion and the plants are very much alive and very much in motion. From the tiniest cell to the largest tree they exhibit constant, pulsating movements. Many of the movements are described through so small a space as ordinarily to escape our notice, but a little observation makes them quite apparent. They all have a well-directed, scientific purpose.

What is plant growth itself but motion upward and outward? If a telescope or an instrument such as Sir Jaghadish Bose’s crescograph be trained on a healthy plant, it is possible to see the growth actually take place before the eye somewhat as it is managed in motion pictures. Travelers aver that if a Banana Plant be cut off close to the ground and the surrounding soil well supplied with water, the sturdy creature will make such strenuous efforts to destroy the effects of its mutilation that its growth may easily be perceived with the unaided eye, and a full-sized leaf produced in a single day.

Leaves and flowers are usually quite mobile. When they go to sleep, they droop and fold their edges together very carefully, sometimes to such an extent as to make themselves almost invisible. Even such an astute man as Linnaeus was once completely deceived by some sleeping specimens of Lotus. They were very fine red flowers and he was proud of them. Taking a friend to view them one evening by lantern-light, what was his dismay to find that they had completely disappeared. He concluded that they had been stolen or eaten by insects and went away, only to find them in full array on his return the next morning. It took several nocturnal visits to unravel the mystery and discover that the flowers folded themselves and retired so adroitly into the surrounding foliage each evening that they were completely hidden.