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these same or similar insects, it is common to bury potatoes with a long stick stuck through them to mark their whereabouts. This is done early, some time before planting. The grubs collect on these to feed, when they are gathered and destroyed. Gas-lime and salt are also highly recommended by experienced gardeners of Europe. These are placed with the seed in planting.
Bruchus pisi, Linn.
Family, Bruchida. Sub-Order, Coleoptera.
This little insect, though doing little damage to garden peas, for in green peas it is not only too small to essentially change the flavor, but even to attract the eye, but in field crops, where peas are raised to feed after they are fully matured, there is very serious injury, for this little weevil, so generally distributed, and so persistent in its yearly attacks, consumes, while yet a larva, all the nutritious material of the pea; leaving only the germ and a mere shell outside. Hence, affected peas will grow, but, of course, with bated vigor; as the needed starch pabulum is wanting in those early days, the precarious time with all life; but to feed, they are almost entirely useless.
The little brown weevil, with the wing-covers so short that some light markFIG. 7. ings, somewhat resembling a letter T, are seen just back of them (Fig. 7.-Bruchus pisi, Linn.), comes through the winter in the peas, having a little opening (Fig. 7, b), a door of exit, already prepared, where they not infrequently remain even to the day of sowing. I have seen them thick as bees above the ground where peas were being sowed. Just as soon as the pods are formed and the seeds set within them, the weevil, big with eggs, if not with mischievous intent, pierces the pod opposite each pea, and inserts an egg within each puncture, so that every pea may contain within the seed of its own destruction. The larvæ, which soon hatch from these eggs, though grubs, being the young of beetles, are legless, and hence resemble maggots, the larvae of two-winged flies, which name is frequently applied to them. These larvæ find the young tender peas rich feeding, and by the time the peas are large enough for table use, are sleek and plump, and can easily be seen with the naked eye; and with a glass, their good feeding qualities are quickly discerned, as their tender skins seem ready to burst. By the time the peas are hard, having already eaten a hole through the shell (Fig. 7, b.), thus showing a foresight not rare among insects, they assume the pupa state, and change to imagoes before the time for sowing or planting the next spring.
As these insects are in the peas in the winter and in the spring, if the same be kept over one year, in perfectly close barrels, bags, cans, or bottles, of course the insects thus confined will all die. Hence, if these pea weevils are sufficiently annoying to cause disturbance, there can be a most effectual estoppel put upon their mischief by thus putting all our peas in close vessels, any time in the winter, and keeping them thus close for one season. If all would do this, and we must have concerted action in this insect warfare,-we should.
soon be rid of this enemy. But the evil will be mitigated if we practice the above simply as individuals; for if the insects do find their way to our fields from those of our careless neighbors, they will doubtless come in far less numbers, and those that do come will very likely be too late to do damage, while we may escape entirely.
THE SQUASH BUG
Coreus tristis, De Geer. Family, Coreida. Sub-Order, Hemiptera.
This old-time enemy is so well known that the figure is all that is necessary to bring his image and evil doings to mind.
The squash-bug, in common with all bugs, passes through partial or incomplete transformations, by which we mean that they are quite alike at all stages of growth, so that usually, at any stage of growth, the species would be recognized by even the unskilled in entomology. The larva, unlke the caterpillar, the grub, the maggot, is so like the imago that the relation of child and parent FIG. 8. is easily recognized. The mature insect (Fig. 8) hibernates during winter, but by the time the melon, squash, or pumpkin vines are well up, their dusky forms, ochre yellow beneath, may be seen feeding on the leaves by day, and hid under some chip, clod, or in some crevice, by night. Soon the brown eggs are laid in clusters glued to the under side of the leaves, and the greenish larvæ, which soon become grayish, which hatch from these, commence a thorough work of despoilation, in which they are aided by their parents, which seem unwilling to die with so much good provision at hard. After a time, stubs of wings appear, which, with increased growth, is all that serves to distinguish these pupa from their former larval condition. Nor can these afford time for quiet, like most pupæ. On the other hand, they continue to gorge themselves with the juices which they suck from the plant. Soon, they attain full growth, and fully developed wings, and are called imagos. These imagos live through the winter and are ready to repeat the same ruinous work another season.
The habit that these squash bugs have of concealment suggests a very practical means to capture them, which was tried here at the college the past season with perfect success. It is similar to the Ransom process for capturing the plum curculio, and consists simply in placing small pieces, boards, chips, or even green leaves on the ground, close around the vines. The bugs appropriate these as hiding places during the night. We may then go around each morning, early in the season, before the eggs are laid, and gather and destroy the bugs thus concealed, and soon extirpate the cause of the evil. These morning visits must be so early that the insects will not have yet left their hiding places. If the eggs are laid before we capture the bugs, we should either gather the eggs from beneath the leaves, or continue the same process narrated above to get rid of the young.
In all cases where mature insects come forth in the spring, of course in limited numbers, as with the potato beetle, the squash bug, etc., we shall save very much by early battle; and if we can persuade our neighbors to engage with us, the late battles and the battles of succeeding years will be but skirmishes.
SQUASH VINE ROOT BORER.
Melittia cucurbitæ, Harr. Family, Egerida. Sub-Order, Lepidoptera.
This insect, a near relative of the peach-tree borer and currant borer, so troublesome along the peach belt, is becoming an evil of considerable magnitude in many parts of our State. It is no new enemy, having worked in Massachusetts and other States east for many years.
The moth, which is a beautiful orange, with deep blue wings, in common with all of this family, flies during the hottest sunshine, and with great swiftness. She lays her eggs during July and August, on the vine, close to the ground. The larva, which would be known as a caterpillar from its possessing sixteen legs, bores the base of the stem and roots, and thus entirely destroys the vines. They pupate in a rough cocoon of earth, about the roots. Dr. Packard has noticed their forming their cocoon in the stem. These are formed in autumn. The imago comes forth the next summer to inaugurate the same round of ruin.
To dig out the borers so soon as discovered, is a sure but tedious method, and the vines are often ruined before the presence of the larva is discovered.
It has been recommended to catch the moths, also to carefully gather the eggs, but I much doubt the practicability of these methods, es
pecially the latter. It is possible, and certainly very desirable, that we might discover some preparation with which to surround the vine, that would be so obnoxious to the moth as to prevent egg-laying. Limited trials of gas-lime, whale-oil soap, weak solution of carbolic acid, and other insecticides might be made. It would be very well to try the remedy given by Secretary Boteham of Ohio to prevent the work of the peachborer, which is given in the description of that pest.
Macrosila quinquemaculata, Haw. All who grow that beautiful and savory vegetable, the tomato, are acquaintel with the formidable pest which,
unless prevented, toooften bring all our hopes of satisfied tomato appetites to naught. Who has not seen the beautiful larva, so fat and gay in its robes of deepest green, trimmed with yellow or white and beaded with the same, and who has not heard of the utterly groundless stories of its fatal horn, whose poisonous thrust it is said brings pain and death?
In July, the beautiful large gray moths (Fig. 9) appear, lay their eggs on the leaves of the tomato, not refusing potato vines in the absence of tomato plants, which they evidently prefer, at which work they may be seen early in the evening. I have frequently caught these so-called humming-bird moths around the tomato plants, or poised above flowers, where, with their long sucking-tube, they seem engaged in extracting nectar.
The greenish larvæ (Fig. 10) though they are not infrequently dark brown, eat voraciously, grow rapidly, and by the last of August they have not only stripped the plants of their foliage, but have become full grown, when they meas
ure three inches in length.
They then go into the earth, where they pupate in an earthen cocoon. The peculiar form of the pupa is a marked character of this family (FIG. 11). These brown pupæ may be found in the earth, a few inches beneath the surface, until
the following summer, when the fine moth again comes forth.
Hand-picking is a quick, easy, and sure preventive. The only objection to this, so for as I know, is that it is disagreeable, and sometimes prevented by timidity. Yet I presume that a good pair of gloves will insure the temerity necessary to its successful practice. As before intimated, the fear is entirely groundless, for there are no more harmless creatures in existence. To be sure they can give quite a sharp pinch with their strong jaws, which they will attempt to do if held, and which I have often experienced while fondling them, but this is almost painless and entirely harmless. They never use their caudal horn, the supposed weapon of immemorial dread. So hand-picking, with or without gloves is entirely safe, and as effectual as safe. Of course the disfigured leaves will guide us in our search.
I have found that skunks are powerful aids in this fight, as they feed extensively on the pupæ.
As a full account of the natural history of the Agrotians has already been given in connection with field crops (see page 109), we need say but little of the -species which is often so ruinous to our cabbage and tomato plants.
As will be remembered, the larvæ generally lie concealed by day just beneath the soil, and come forth, cloaked in darkness, to do their evil work. This is not strictly true, as frequently, on cloudy days, their eager appetites, or else an innate longing for destruction (for these cut-worms do seem the most totally depraved of all insects), impel them forth to work havoc. I have known sixty tomato plants cut off between the hours of 3 and 6 P. M.
Sandy gardens, and those near meadows, pastures, or lawns, where the insects have commenced and nearly completed their growth by feeding on the grass or its roots, are by far the most liable to attack.
After the ground is well fitted for the plants, great advantage will result from placing newly mown grass, fresh cornstalks, etc., in heaps about the plat. Coming to these by night, the larva will feed and crawl beneath, and may be captured and destroyed each morning. I have known large numbers to be thus entrapped. Securing those immediately within the ground to be planted, however, is not alone sufficient. These larvæ have not sixteen legs for nothing, and especially is there danger from immigrants if grass is grown contiguous to the ground planted. It might be well to continue, in such a case, to place the bunches of grass around the border of the planted area, to still attract these night marauders.
Sized paper, such as we usually write on, wound closely about the plants, and held in place by banking slightly about the base with earth, is a sure preventive, as the larvæ can not pass up its smooth surface. I have known this to be practiced with the happiest results. Care is only necessary that the paper may closely encircle the plant, and that the banking be so efficient as to surely hold it in place.
Hand-work, digging out the larvæ, is always to be commended. No more injury need be expected from these troublesome "worms," if they are once in the grasp of an irate gardener, who is disgusted at seeing his plants prostrate upon the earth. And it must give rare satisfaction to dig the culprits out from beneath the plants which their rapacity has simply cut asunder and left to wilt, and aggravate the owner, who had already reckoned up and planned to expend the proceeds from the same mutilated plants.
Here, too, especially on light soils, it will be wise to set a superfluous number of plants.
Plutella cruciferarum. Family, Tortricide. Sub-Order, Lepidoptera.
While treating of cabbage insects, I might describe the cabbage leaf-roller, or Cabbage tineid (Plutella cruciferarum), which little green "worms," or more properly caterpillars, mine the cabbage leaves quite disastrously, and which gray moths, with a white stripe along the back, are quite too small to produce alarm, and yet are the parents of the same green larvæ. But I will only say that I have never been troubled with them, nor have I seen much of their work. If they are annoying, it would be well to try plaster with a little turpentine mixed in, whale-oil soap solution, lime, nor should I fear to experiment with a little powdered white hellebore.