Here then was a new branch of investigation, a new field of study to be entered. He was not an entomologist, nor could he gain any assistance from his friends who were such, because, though they were scientific, and able to assist him in names and descriptions of the insects presented, still they were not practical entomologists; their knowledge of these creatures was purely scientific, and while they could descant learnedly upon the systems set up by the great masters of the science, for the most perfect classification of insects, they could render us practical men but little aid in combatting our insect foes. Great assistance they have rendered, however, in providing names for all these wonderful creatures, in describing their habits and their economy, and in assigning them places in the beautiful classification that has been provided for them.
On turning from men to books, but little more assistance or encouragement was met with; these too would only give the names, the places, and the descriptions, in the most approved language of the science, but they are not attractive nor intelligible to the unlearned. Any person can soon acquire the language of the science, with a little study, but these scientific books do not give us directions how to rid ourselves of the pests.
Among the books that are accessible and that are adapted to the general reader, and to the student of practical entomology, two were found of eminent utility as far as they went. These are the excellent reports to the Massachusetts and the New York Agricultural Societies, by Messrs. Harris and Fitch, which are clothed in popular language, and which treat particularly of the insects injurious to vegetation, and they put us in the way of combating our foes. The former, which has been reprinted and illustrated in beautiful style, is worthy of a place in every farmer's library, and will prove a valuable aid in the study: the latter is printed in connection with the Society's reports. To both of these, the author acknowledges his indebtedness, and from both has he drawn liberally.
Other popular treatises, though attractive, have proved of very little practical value, and the student will find even the reports above referred to imperfect, as they were prepared for a limited region, and do not mention several insects that are common in other parts of the country than the States for which these reports were prepared. It were much to be desired, that every State Society would have similar reports, respecting the insects, peculiar to its state.
Thus the author found himself compelled to investigate this broad field of study for himself—it became necessary to grasp the elements of the classification, and to go into the field and the orchard, to use his eyes, and to observe for himself. This was a labor of time, and required considerable effort; but it brought its own reward in the pleasure attendant upon this delightful study. At the same time there was great satisfaction in the thought that all these facts, gathered from the works of men of science, confirmed by personal observation, and rendered useful and applicable in practice by his fellow laborers in the garden and orchard, would be a valuable contribution to them, and would constitute a useful portion of the American Pomology he was then preparing.
Unfortunately for himself, he has discovered that his collections, in this department, covered several hundred pages of manuscript, and that, if printed, they would render his volume too cumbrous. Upon consulting with his publishers, it was concluded best to lay the matter aside, for the present at least, and to prepare anew a brief account of some of the insects most injurious to the orchard, with short suggestions as to the best methods of combating their ravages. This conclusion has been the more readily yielded to, because the public now have a medium of communication with the scientific entomologists, which well supplies the great want we had begun to experience. I refer to a monthly publication, issued by the Entomological Society of Philadelphia, in which the questions, that are constantly occurring to farmers, are answered in the most simple, clear, and satisfactory manner.[23] Besides this, we find in our best agricultural journals, a page or a column, devoted to the consideration of insects injurious to vegetation.[24]
For the sake of convenience and system, these notes will be presented in the order of the approved classification of insects. Omitting further introduction or discourse upon the wonderful instincts and habits of insects, and explanation of their metamorphoses and the principles of classification, and confessing my poor qualification for the task, let us proceed at once to the catalogue.
COLEOPTERA.—Beetles.
In this class of insects we find both, friends and foes. The former assist us by their voracious appetites, that can only be satisfied with gourmandizing upon other insects, particularly the juicy bodies of their larvæ. The latter embrace some of our most troublesome pests, especially as they consume vegetable matters, in the perfect as well as in the larval condition, and in both stages are exceedingly voracious. Moreover, they generally commit their depredations under cover, or at night. Some live in the soil and consume the roots of our plants, and others mine their way into the solid wood of the stems of our finest trees; while some only affect the twigs and smaller branches, and others devour the foliage, flowers, and fruits. A few of the most familiar and troublesome of these will now be introduced; and allusion will also be made to some of those which befriend us by their destruction of other insects.
Saperda bivittata. (Say.)—The Apple Tree Borer.—This is a nocturnal insect, which has been found very destructive to our orchards. The female deposits one egg in a place, generally low down on the stem of the tree; this hatches, and enters the tissues of the bark, where it feeds for a time, a footless grub. As it grows, it burrows deeper, and upward, until it reaches the sap wood, upon which it feeds. When half grown, it burrows still deeper, and upwards into the heart of the tree, and then outward through the sap wood to the bark, but retires again toward the centre, as to a place of safety, to undergo its transformation, after packing the hole with shreds of wood and with its castings to make its retreat secure. In the spring, the perfect insect opens its way outward, and emerges to the light of day.