SEEDING AND PLANTING

SEED SUPPLY

It has been shown in a previous chapter that the owner of deforested land who desires to secure a second crop may find it necessary or cheaper to adopt artificial measures wholly or in part instead of depending upon natural reproduction. These measures may be of two kinds—direct seeding, in which the seed is sown where the trees are to stand permanently, and the planting of trees grown in nurseries.

Whether artificial reforestation is accomplished by means of sowing seed or planting trees, the first requisite is a supply of tree seed of the desired species and of good quality. Unfortunately for the timber owner who wishes to enter upon extensive seeding operations, the business of collecting and preparing forest tree seed for market has received but little attention from old-established seed firms, and it is not always possible to purchase the species and quantity desired. Moreover, the prices charged are often excessive.

In the Pacific Northwest, however, the demand for seed of Douglas fir and Sitka spruce has led to the establishment of a considerable trade in these species, and at reasonable prices, so that where these species are to be used, or only small quantities of other species, the timber owner will probably find it to his advantage to purchase the seed rather than to attempt collecting it himself. Douglas fir seed is quoted at $1.40 to $2.00 per pound and Sitka spruce seed at $2.25 to $3.00.

In purchasing seed it is common practice to specify that it shall be of the new crop, because tree seed kept in ordinary storage loses its vitality materially. When properly stored in air-tight receptacles, however, as is now done by some seed dealers, it will retain its germinative power for several years with only slight depreciation. Moreover, fresh seed, if improperly treated, may be of very poor quality, so that the age of the seed is of little value in the determination of its worth and the only sure method of ascertaining this is by means of germination or cutting tests. The latter method is the quickest and most simple and consists of cutting open a number of the seeds and ascertaining the per cent whose kernel is sound, plump and moist. Seed of good average quality should contain not more than 25-30 per cent of infertile seed.

When seed cannot be purchased, it is necessary to collect. Since no species of coniferous trees bear abundant crops of seed each year and often several seasons will elapse between good crops, it is necessary to gather sufficient seed when the supply is abundant to provide for succeeding years when the crop is apt to be a failure.

The seed ripens in the fall, usually during August or September, and the cones should be collected at that time. Pines require two years in which to mature the seed; that is, the cones are not fully formed and the seed ripe until the second fall after the fertilization of the flowers in the spring. Most of the other important conifers ripen their seed in the fall of the same season. Shortly after the seed is ripe, the cones open and allow it to disseminate, consequently they must be gathered before this occurs.

The cones are gathered either by climbing the trees and cutting them off from the branches, by picking from the tops of felled trees, or by robbing squirrels' hoards. Where squirrels are abundant in the forest, the last method is the cheapest. Climbing trees is practiced only where the trees are small. When this method is employed, the workmen should be equipped with linemen's belts and climbers. Picking from felled trees is readily carried on except where dense underbrush interferes, as is the case in the ordinary Douglas fir forest.

Trees growing in the open, with large crowns extending down the greater part of the bole, bear cones more abundantly than trees in dense forests, and for this reason collecting from scattered open growths can be done more cheaply than on logging areas. Often large quantities of cones can be purchased from settlers who will collect and deliver them at central points at a stipulated price. When this method is employed, however, frequent examination of the cones should be made to ascertain that they contain the full number of seed, for often opened cones from which a part or all of the seed has been disseminated will be offered for sale. Insect larvæ also often destroy a large proportion of the seed, particularly when the crop is light and care should be taken that the cones purchased are not infested. The prices paid for cones vary from 25 cents to 50 cents per sack for the larger cones, like yellow and white pine, and 50 cents to $1.00 for Douglas fir and spruce, depending upon the abundance of the crop.

After the cones are gathered the seed must be extracted and cleaned. Where climatic conditions in the fall of the year will permit air-drying, the cones may be spread out on sheets or blankets where they will be exposed to the sun and wind. Under this treatment they will open in from 3 to 6 days, depending upon the weather and the species. Where bad weather will interfere with air-drying, the cones must be dried undercover by artificial heat. This is the method usually employed by professional seed collectors, and where large quantities of cones are to be treated each year special dry houses are constructed and fitted with elaborate drying apparatus. The work can be done most cheaply with such an establishment, but for the ordinary timber owner who expects to collect seed only occasionally, a makeshift dry-house which will answer the purpose can be fitted up inexpensively in any unused building. The essential features are shelves or trays 4 feet wide arranged around the walls of the room, one above the other and separated about 8 inches apart, and a heating stove placed in the center of the room. The shelves may be made of burlap stretched tight, or, better still, of wire screening of 1-1/2 inch or 3/4-inch mesh.

After being subjected to a temperature not exceeding 110° Fahr. for from 24 to 48 hours, the cones will open, allowing the seed to fall out when shaken or pounded. The seed when separated from the cones is then mixed with a coarse gravel in about the proportion of 4 to 1 and churned to remove the wings. Finally, all foreign matter is removed by screening and hollow seed blown out by passing it through an ordinary fanning mill.

SEEDING VERSUS PLANTING

The selection of the method of reforestation to employ, whether direct seeding or planting, depends primarily upon the character of the area to be restocked. Direct seeding is usually considerably cheaper when the results are satisfactory, but only on the more favorable sites where moisture and soil conditions are right is there any assurance of success. Even in such cases partial or total destruction of the seed often results from birds and rodents. In exposed situations where the soil is shallow, or where because of climatic conditions soil dries out several inches deep during the growing season, the seed may not germinate at all, or the young seedlings may be killed before they have time to send their roots down to the permanent moisture level. In such situations, planting is the only reliable method. If the plant material is of the proper kind and the work well done, satisfactory results are almost certain to follow. Direct seeding is a much more rapid method than planting, and where extensive areas are to be restocked within a short period and seed is abundant, the work can be completed quickly. On the other hand, this method is wasteful of seed because a large proportion fails to germinate and the young seedlings often succumb to adverse conditions, so that where seed is scarce or its cost high, planting is the more practical method.

Because planting is the most reliable method it has been the one most largely employed in extensive operations, both here and in most European counties, but thorough tests are now being made of direct seeding and under proper conditions it promises to be fairly satisfactory. The Douglas fir region west of the Cascade Mountains offers the most favorable conditions for direct seeding and except on badly exposed south slopes, or where the growth of brush is exceedingly dense, it is believed this method will prove a satisfactory one for the timber owner to employ.

In the yellow pine regions conditions are not so satisfactory for direct seeding, since this tree occurs largely in a region of deficient rainfall. However, natural reproduction is abundant throughout many portions of this type, and it is probable that direct seeding will prove fairly successful if the proper methods are employed and if forest conditions have not been too greatly disturbed. That some method of successfully employing direct seeding with yellow pine be found is greatly to be desired, since yellow pine seedlings do not withstand transplanting well, but there is need for careful experimentation before extensive seeding operations in this type by private timber owners would be justifiable.

Western white pine, it is believed, will be easy to reproduce in most of its native situations by direct seeding, though the greater scarcity of its seed and the fact that it will be more subject to destruction by birds and rodents because of its larger size may make planting the more practical method.

Trees for planting can either be purchased from commercial nurserymen or grown in nurseries established for that purpose near the planting site. When only a few thousand trees are needed it is cheaper to purchase them, but when extensive operations are contemplated, covering hundreds of acres in which millions of trees will be needed, it is far preferable for the owner to grow the trees in his own nursery. Some initial outlay for the establishment of the nursery will be necessary and a practical nurseryman should be employed, but the saving in the cost of the trees will fully compensate for these.

One, two and three year old trees, the latter once transplanted, are usually employed in planting, the older trees being used for the less favorable sites. In planting they are placed in rows equidistant apart, the spacing varying from 4 to 12 feet, with a general average of about 6 feet. The work may be done either in the fall after growth has ceased or in the spring before growth commences.

The cost of planting, of course, will vary greatly with the age of the trees, the number planted per acre and the accessibility and character of the planting site. With young trees and wide spacing, the cost may be as low as $6.00 per acre, while in more unfavorable situations where older plants are used and planting is more laborious it may be as high as $16.00. A fair average, however, for those areas which a timber owner would be most likely to plant up is about $8.00 to $10.00 per acre.

In direct seeding, several different methods may be employed, such as broadcasting over the entire area with or without previous preparation of the soil, sowing in strips, or sowing in seed spots; but observation and experiment have shown that it is necessary for seed such as Douglas fir, yellow pine and western white pine to come in close contact with the mineral soil in order that it may germinate and the seedlings live; consequently only those methods should be used which will accomplish this. Where the area has been burned over previous to sowing and the mineral soil laid bare, broadcast seeding may be employed. Where the ground will permit the use of a harrow good results are obtainable by scarifying the soil in strips about 10 feet apart and sowing the seed in these strips. On unburned areas covered with a dense growth of fern, salal, moss, grass, or other plants, this covering must be removed by the seed spot method. This consists in removing the ground cover with a grub hoe or mattock in spots of varying diameter (6 inches to 3 feet) and of various distances apart (6 to 15 feet), and sowing the seed in these spots. The advantages of this method are that a minimum amount of seed is used; the ground can be prepared and the seed covered to whatever extent is desirable, and the soil pressed down. This method is believed to be the one best suited to the greatest variety of sites.

The amount of seed used per acre will, of course, vary with the species and the method used, and the quality of the seed. The following table indicates the approximate quantity of seed of good average quality required per acre for three different methods, the average cost when collected in fairly large quantities, and the number of seed per pound:

No. pounds required per acre.
Species. No. seed per lb. Cost per pound. Broadcast, entire area. Strips. Seedspots 6' apart.
Douglas fir 42,000 $1.50 2–3 ½–1 ½–¾
Yellow pine 8,000 .50 10–12 2–2½ 1½–2
Western white pine 14,000 .75 6–8 1½–1¾ 1–1½

The total cost, too, will vary widely, not only because of the different quantities of seed used but also because of the great extent to which the methods are varied to suit the conditions occurring upon the area. Simple broadcasting without any preparation or treatment of the soil will not exceed 20 cents to 25 cents per acre for labor; harrowing and sowing in strips, 85 cents to $1.10 per acre, and sowing in seedspots, $2.00 to $5.00 per acre. Upon this basis the total cost per acre will approximate the figures given in the table below:

Species. Broadcast over
entire area.		Strips. Seedspots,
6' apart.
Douglas fir$3.20–4.75$1.00–2.60$2.75–6.00
Yellow pine5.20–6.251.85–2.352.75–6.00
Western white pine4.70–6.252.00–2.402.75–6.00