American Pomology - Part 18
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Part 18

=Erythroneura vitis=, (_Harris_), or the Vine-leaf hopper, is pale yellow, with two broad blood-red bands, and a third dusky one on the apex. Swarms of these small insects occur in August, and often bleed the foliage so as to injure it seriously.

=Erythroneura tricincta=, or the Three-banded Leaf-hopper, is like the preceding species, but the bands are narrower.

=Erythroneura vitifex=, or the Vine-destroying Leaf-hopper, is yellowish-white; the wing-covers have oblique confluent, blood-red bands, and a short, oblique, black line on the middle of their outer margin. The thorax commonly has three red stripes, the middle one forked anteriorly and confluent, with two red stripes on the crown of the head. When the wing-covers are closed, they look red, with a cream-colored spot, shaped like a heart placed anteriorly, and on the middle, a large diamond-shaped spot, with a small red spot in its centre.

These insects are sometimes seen in such numbers upon the grape vines in September, that, when the leaves are disturbed, they fly out and resemble a shower of snowflakes. The young resemble their parents, but are dest.i.tute of wings.

A REMEDY is much needed.

=Erythroneura vulnerata=, (_Fitch_), or the Wounded Treehopper, is tawny yellowish, sometimes tinged with red; the wing-covers have white spots and veins, and on the middle of the outer margin an oblique black streak, between two creamy white spots; the hind one smaller, and an oblique blood-red line at its end; tips smoky-blackish; length 0.12 inch; September.

=Otiocerus Coquebertii=, is a slim fly of yellowish-white color, with a bright carmine-red stripe along each side of the body and wings, which are widely forked behind. Length 0.42 inch; July until autumn, on the wild grape vine.

There are a great many insects of this order, which are familiar to most country residents on account of their unpleasant smell. These are the true bugs, and belong to the sub-division called _Heteropterous Hemiptera_. The Squash-bug is a familiar ill.u.s.tration of these insects; it is called the _Coreus tristis_, from its sad dull color; they are quite destructive to all plants of the Squash family.

=Reduvius trinotatus=, is one of this order, which is a valuable aid to the horticulturists, because its sucker is armed with sharp instruments, that enable it to pierce and consume other insects, many of which are destroyed by it. This insect has been introduced into the West for the sake of its valuable services.

ORDER LEPIDOPTERA.

The insects of this order are very numerous, and in their larval or caterpillar state they are often very destructive. In the perfect form of b.u.t.terflies and moths, they commit little or no depredations, because their jaws have been transformed into a sucking apparatus.

They consume, in their perfect state, little else than honey.

The order has been divided into three great sections: b.u.t.terflies, _Papiliones_; Hawk-moths, _Sphinges_; and Moths, or _Nocturnes_. Of these, the _aegeridae_ const.i.tute a very distinct family, resembling bees and wasps rather than b.u.t.terflies; their caterpillars also differ, being borers, and nearly naked. b.u.t.terflies are produced from caterpillars that are not generally very injurious to our crops.

Hawk-moths are large insects, and have great power of flight; their caterpillars are large and voracious. It is the moths proper, a very numerous family, which do us the most harm, and which will demand the largest share of our attention. They vary much in size and appearance.

Some of the females are dest.i.tute of wings.

The _Arctians_ or Woolly Bears, are a very numerous division of the tribe of _Bombyces_ or Spinners, so called from the name of the Silk-worm; some of these will be mentioned.

=Orgyia leucostigma=, or the Vaporer Moth, is a very beautiful caterpillar, frequently seen upon our fruit trees, though not confined to them. They feed separately, and therefore we can best destroy them in the egg. Fortunately, these may easily be found during the winter, for the female, being wingless, never quits her coc.o.o.n, but deposits the eggs in a ma.s.s upon the outside of it. The whole contrivance is one of the many ill.u.s.trations of the wonderful instinct of insects.

When about to spin, the worm secures two or more leaves, by entwining her silk about their stems, and also around the woody twig upon which they grow; she then attaches them together by bands of silk, and spins her coc.o.o.n between them. She thus secures a winter resting place for her eggs, and her progeny, when they hatch the next summer, are upon the tree that furnishes them their appropriate food. These dead leaves will attract our attention during the winter, and should be gathered and burned. Many of the caterpillars are destroyed by a little Ichneumon-fly.

=Orgyia antiqua=, or the Rusty Vaporer Moth, of Europe, has been introduced into this country, and has been quite destructive to thorn-hedges in Rhode Island. They may become troublesome to our orchards.

Several of these _Arctians_, or Tiger-moths, may be seen about our houses on a summer evening, as they are chiefly nocturnal. One of the most common is

=Arctia phalerata=, or the Harnessed Moth, so called from the markings on its wings. Another distinctly marked one is _Callimorpha militaris_, now called _C. Lecontei_. Beautiful ill.u.s.trations of these are given in Dr. Harris' Report.

=Spilosoma Virginica=, is the beautiful White Moth, or "Miller," that we see in May; it is the imago or perfect insect of a large hairy caterpillar, of a yellowish color, frequently seen in our gardens, and quite destructive to vegetation.

=Hyphantria textor=, or the Fall Web-worm, is very troublesome upon shrubs and trees during the summer and fall. They are called the Web-worms from their habit of feeding gregariously in large numbers, and spinning a web that envelopes the leaves and the whole branch, as they devour the foliage.

This insect commits sad ravages upon our cultivated trees of various kinds, for it is not a choice feeder, consuming but one species, like many other insects. Their most common pasture is the mulberry, and the related Osage Orange is frequently attacked. The Elder bushes appear very attractive to them, and are often covered with their unsightly webs. Elms suffer very much; our favorite fruit trees are attacked; apples, pears, cherries, quinces, and, occasionally, even the peach trees are eaten by them. Even the repulsive Ailantus, which has often been recommended as a wormless tree, is greedily devoured by these caterpillars, notwithstanding its disagreeable odor.

The eggs, from two to three hundred in number, are deposited on the under side of a leaf, near the end of a twig. These soon hatch, and the larvae commence feeding on the upper surface, spinning their threads from side to side, and then, attaching two or three leaves together, they soon make a web. They continue feeding and spinning along the twig, as they consume the tender portion of the leaf, leaving the mere skeleton.

The caterpillars are small, of a pale yellow color, with a broad blackish stripe on the back, and another beneath. They are thickly clothed with whitish hair; the head and feet are black. Worms of the same nest vary in size and colors. When about an inch long, they disperse, and spin their coc.o.o.ns. The moth is milk white, without any markings on its wings, and is 1.25 to 1.35 inch in width. (Vide Harris, p. 358).

Though called the Fall Web-worm, these caterpillars appear about Cincinnati in the end of May quite abundantly, and from that time until October, they are more or less frequent; most so in August. In the North, they may be later; I have seen large tracts of forest defoliated on the lake sh.o.r.e, in August, 1865.

REMEDIES.--For the destruction of these pests we must resort to hand-picking, when they are in the caterpillar state. The twig or branch should be taken off, and the worms crushed or burned. It is fortunate for us that they are gregarious and that they spin a web, for we can detect them while they are yet young, and when confined to one or two leaves, so that the whole brood may be destroyed with very little effort. Birds, and some insects, aid us in keeping them in check.

=Clisiocampa decipiens=, (_Walker_), or _C. Americana_, (_Harris_), is commonly known as the Tent-caterpillar, or Nest-caterpillar. The larvae are not indiscriminate feeders, but prefer the foliage of certain members of the _Rosaceous_ family of plants. Their natural food appears to be the common wild cherry, but they attack the apple so vigorously, that they are often called the apple tree worm. Mr. Fitch thinks they do not feed upon the peach; but I have frequently found them upon this tree since 1855. The moth appears to be endowed with wonderful instinct in depositing her eggs; selecting a terminal shoot that has completed its growth, they are placed to the number of 200 or 300 around it in a broad ring or sheath, and covered with a sort of varnish that protects them.

Very early in the spring, when the buds of the apple have just begun to swell, the eggs hatch, and the little worms traverse the twig, spinning a slender thread; when they reach another branch, they halt in the bifurcation, and, moving about, soon create a slight web with the silken threads, and from this they emerge in search of food, spinning a thread along their route, and when they return, they travel about, and thus enlarge their web.

REMEDIES.--These insects may be attacked in the egg or in the larval state. The former are so arranged as to be conspicuous on the naked spray at any time during the winter--whenever seen, they should be broken or cut off, and carried to the fire. In the early spring, we must watch for the little tents in the bifurcations of the limbs, and remove the nests with all the worms; this may be done when they are small, by using the thumb and finger; if larger, it is a disagreeable task, but no orchardist should hesitate when he recollects that six hundred leaves is a day's ration for one colony. They can easily be gathered in their web, thrown upon the ground, and crushed with the foot. Mr. Needham, of Ma.s.sachusetts, has invented, what he calls, a caterpillar scourge; it is a little cone of wood, clothed with a piece of wool-card. This is attached to a pole: when thrust into the web, the whole nest is gathered by the card-teeth and brought down. An old dry mullein stalk has often been used for the same purpose, and some recommend burning the nest, or shooting it; but I have more faith in thumb and finger work, believing it to be more thorough.

Among the natural enemies of these caterpillars are the Tiger-beetles, which a successful orchardist of Illinois uses systematically for their destruction. He catches a beetle, and puts it upon a tree containing a nest of the Tent-caterpillar, after which he finds the worms soon disappear.

=Gastrophaca Americana=, (_Harris_).--The Lappet-caterpillars are found on apple trees. The worms are flat, and when at rest on a limb, they often escape observation from their gray color resembling the bark. A fringe of hairs, along their sides, gives them this flat appearance. They feed only at night. Dr. Harris found some in September that measured two and one-half inches in length, and above half an inch in breadth.

SATURNIANS, CERATOCAMPIANS, ZEUZERIANS.

=Platysamia (Attacus) cecropia=, (_Linn._), the Cecropia Emperor Moth, is found as a large cylindrical, pale green worm, three or four inches long, and as thick as one's thumb, and having two rows of pale blue, projecting points along each side, and two rows of pale yellow ones upon the back, with four larger, bright orange, or red ones anteriorly, all ending in little black p.r.i.c.kles. The moth is large; its wings dark gray; each has a large white, crescent like spot in the centre, margined with red, and a red band crossing both wings. Appears in June; width five to seven inches.

There are others of this family of n.o.ble moths whose names have been indicated above, but they are not very destructive to the orchard.

Then come, in Dr. Harris' cla.s.sification, the _Zeuzerians_, a group of moths which, like _aegerians_ among the Sphinges, pierce the roots and stems of trees. Among these is _Xyleutes (Cossus) robiniae_, or the Locust-tree Boring-moth.

The Saturnians are a group of large, naked caterpillars, which are generally short, thick, clumsy, and cylindrical; they are leaf eaters, and some of them, when young, keep together in families, but separate as they become older, when they spin large silky coc.o.o.ns sometimes among leaves, which they secure by silk to the twigs, sometimes attaching them to the stems and limbs, and at others at, or beneath, the surface of the ground. This group contains some of the largest and most beautiful moths, with large woolly bodies, and widely extended, highly colored and ornamented wings. They lay a great many eggs; some females deposit several hundreds. Still they are seldom so numerous as to commit serious devastations.

"Among these are the _Telea Polyphemus_, _Tropae aluna_, _Callosamia Promethea_, _Platysamia cecropia_, (formerly known under the genus _Attacus_, which is now restricted to the immense _A. Atlas_, and another species of China), and the _Euchronia Maia_, and _Hyperchiria varia_, (formerly known under the genus _Saturnia_, which is now retained for several European species). The latter species, (_H.

varia_), has been generally known among us under the name of _Saturnia Io_, but according to Dr. Packard, (who published 'a Synopsis of the Bombycidae of the United States,' in the Third Volume of the Proceedings of the Entomological Society of Philadelphia), our species has been confounded by authors with Cramer's species '_Io_,' from South America, and which belongs to a different genus."--[E.T.

Cresson, Mss.]

These moths may yet become valuable for the production of a kind of silk, as they are enclosed in large coc.o.o.ns, the fibres of which surpa.s.s those of the Silk-worm in strength, and might be employed in the formation of fabrics, similar to those manufactured in India from the Tusseh and Arrindy Silk-worms, the strength and durability of which are proverbial. Mr. Pullein, who experimented with the coc.o.o.ns of the _Cecropia_ found that twenty threads of this silk, twisted together, would sustain nearly an ounce more in weight than the same number of common silk.--(Vide Harris, pp. 295-303.)

_Psychidae_ are curious caterpillars, which, being naked, cover themselves during the larva state with a case that protects their bodies, though open at both ends, and which they carry about with them; these cases are made up of fragments of leaves, generally the stems and veins, which they connect together by threads of silk. The Germans call them Sack-bearers. Huebner called them _Canaephorae_, or Basket-carriers, because the cases, often made of little sticks, resemble a basket. One genus is called _Oeceticus_, or House-insect; and the common species, which, in some parts of the country, commits great devastation upon the leaves of trees, is called the Drop-worm, or the Basket-worm, in many places.

We have several genera and species belonging to this sub-family, the most common of which are the _Thyridopteryx ephemeraformis_, and _Oeceticus coniferarum_. The best means for the destruction of this pest consist in persevering efforts for their individual destruction; each case should be cut or torn off in the winter, when they show very plainly upon deciduous trees; they may be crushed, but had better be committed to the flames.

The Notodontians are so called from a hump or horn, which rises from the top of the fourth ring of the caterpillar; the tail is always raised when the insect is at rest. One of these is called, from its horn, _Coelodasys (Notodonta) unicornis_. Some species consume the foliage of our fruit trees, particularly the apple and quince; one of these, the _Datana ministra_, (the _Eumetopona ministra_ of Fitch, or the _Pygaera ministra_ of Harris), will be noticed below.

=Eudryas grata=, and =E. unio.=--The Beautiful Wood-nymph, and the Pearl Wood-nymph.--The worms are very much alike, and resemble the Spotted Forrester. The moths come forth in July; the fore-wings are milk white, bordered behind and on the outer side, from the base to the middle, with rusty brown, edged on the inner side with greenish olive; hind-wings nankeen yellow, with a blackish-brown border. These worms are best removed by hand-picking.

=Datana ministra=, or the Hand-maid Moth.--The moths are troublesome visitors to the evening student in June; they are brown, hairy, thick-bodied, and measure rather more than an inch across the wings.

This creature is destined to give us a great deal of trouble by her progeny, for she deposits her numerous eggs on the under side of the leaf on a twig of quince, apple, and cherry trees, where they hatch into worms, that, during their existence of about four weeks, consume immense quant.i.ties of foliage, often stripping the trees bare.

The worms feed gregariously, lying side by side in solid phalanx. They are of a dark brown in their younger state, but become lighter and more clearly marked at each successive moulting, so that they are distinctly striped with black and yellow. The peculiar character of this worm is, that when at rest, the head and tail are carried up in the air, or recurved over the body, which is supported by the six prop legs placed near the middle. When disturbed, these caterpillars often throw their heads from side to side, as though in anger. They are sparingly furnished with hairs, and they spin but little; though when young, the worms will sometimes drop from the leaves when disturbed, and hang suspended by a fine strand of silk. At full size, these creatures are an inch and three-quarters to two inches long, and as thick as a goose quill, so that we can readily imagine the amount of destruction which may be committed by one of these armies or family groups of one to two hundred worms.

TREATMENT.--Constant vigilance is required on the part of the orchardist, and unremitting efforts while the insect is in the larval condition. Fortunately for us, their habits are such as to aid us in a remarkable way. They may be looked for in July, but they become numerous only about the end of August, and in September. Some late broods may be seen on the access of early frosts, but by the end of September, the worms generally perfect their growth, and descend into the earth to undergo their changes for the next season, when the moths will again appear.

When we may be inspecting our orchards, in the summer and autumn, we should observe any defective foliage, as this is often an indication of the inroads of insects. If our trees have been neglected, we may be alarmed by observing some of the thriftiest shoots and branches quite stripped of their leaves; and, lying along the stems, or crowded together, we shall see these unpleasant worms, unless they be foraging upon an adjoining, or sometimes upon quite a distant branch; for, in changing their pasture, they descend one twig and pa.s.s out upon another, which may diverge considerably from the first.