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Haltica striolata, Fabr. Family, Chrysomelida. Sub-Order, Coleoptera. There is a flea-beetle, too (Haltica striolata, Fabr.), which I have found to puncture the leaves of cabbages, and is thus quite destructive to young plants. It also works on radishes, turnips, etc.
This beetle is of a shining black color, with two waving lines of buff along FIG.12. the back, one on each side, is very small, less than one-tenth of an inch in length, but is so active, briskly leaping away at the least disturbance, that though so small it can hardly escape notice (Fig. 12.) These beetles often fairly swarm on young plants, and at such times do considerable damage.
In England, where a nearly related beetle has long given annoyance by attacking cruciferous plants, lime, soot, and even ashes are recommended as securing the plants against the ravages of these pests. I have tried these remedies, but without perfect success. Still, I think they are to be recommended. Anything which promotes vigor of growth is, of course, desirable, for vigorous plants are far less liable to suffer destruction.
By sweeping a fine gauze net over the plants, large numbers of the insects may be caught and destroyed.
OTHER CABBAGE MOTHS.
I might speak of the larvae of various moths which feed on the leaves of the cabbage, but as there are none in our State sufficiently numerous, so far as I am informed, to do any great damage, and as this report is only to deal with the practical, and as hand-picking is a sure, if it is sometimes a tedious remedy, in all such cases, I will not delay at this time to go into details as to these several species.
Pieris rape, Schrank. Family, Papilionida. Sub Order, Lepidoptera.
In describing the rape butterfly, I shall depart from my usual practice at
this time, and describe an insect not yet among us, for though not a practicai subject with us yet, it is likely soon to be, as this latest arrival from England is fast nearing our own beloved State, and without doubt will soon be one of the worst pests of our gardens. What would we think of a report of like design, to be published in Massachusetts, that should fail to give the fullest practical information as to the Colorado potato beetle?
HISTORY IN THE UNITED STATES.
This species, imported from England, was first taken around Quebec, in 1859, since which time, according to Canadian authorities, it has destroyed annually, about Quebec alone, $240,000 worth of cabbages. From thence it has spread rapidly to the south and west, and has already reached western New York, and perhaps even now is entering our own State.
This butterfly is white, spotted with black,
resembling very much our old speckled white cabbage butterfly (Pieris pro
todice, Boisd.), though, as will be seen by the figures (Fig. 14, inale, Fig. 15, female), the spots are better defined, while usually there is less black.
This larvæ (Fig. 16, a) is pale green, finely dotted with black, and when mature, one and one-half inches in length, while the larvæ of our old spotted butterfly is blue, striped with yellow.
The chrysalis (Fig. 16, 6), which fastens under a board or clod, attaches at one end, and fastens a silken band around near the other extremity. It is brown, while the old one is gray. I am thus particular in this description, as it is imperative, that we may know the enemy at the first onset, so as to give quick battle.
These butterflies, like both species of our common white ones, are two-brooded. The first butterflies appear early in spring, in April or May. After pairing, the eggs are deposited on the under side of the cabbage leaves. These hatch, and the larvæ feed on the leaves, assume the chrysalis state, and the imagoes come forth again in June or July. The second brood behave similarly, except that they remain as pupa or chrysalids through the winter.
a larva; o chrysalis.
As these butterflies are slow fliers they may be caught in a net, and thus the whole evil nipped in the bud. Perhaps it would be well to collect the eggs,-— the larvæ could be picked off,-but the easiest method is to make use of their habit of pupating beneath a board or other object. By keeping the cabbage patch free from rubbish, which every neat gardener would do any way, and then placing boards horizontally above the ground a few inches, letting them
rest on banks of earth; or better, nailing them to perpendicular boards of the same width, like a common bench. These, distributed among the cabbages, will form a resort for the larvæ in which they will become chrysalids. These chrysalids should then be gathered and destroyed. Were these measures to be generally adopted, we should make short work of a prospective insect evil of the first magnitude.
The evil from the cabbage butterfly is likely to be greatly mitigated among us by a parasite which also pupates in the pupa skin of the butterfly. No pupa containing these should be destroyed.
THE RADISH FLY.
Anthomyia raphani, Haw. Family, Muscido. Sub-Order, Diptera.
The various species of this genus are very annoying in our State, and especially so on sandy soils. In the spring, when we so long for fresh vegetables, and feel our mouths fairly water in prospect of the beautiful tender radishes, it is almost as disheartening as a bank failure to find that the coveted morsels are all ruined by a disgusting maggot.
The small, ash-colored flies, very like the onion fly (Fig. 13), doubtless hibernate, though some may pass the winter as pupa. However this may be, the flies are around early in the spring, for our earliest radishes are the ones nost liable to suffer from attacks. The eggs are laid on the stem close to the ground. These soon hatch, and the whitish, footless, conical larvæ, very like the onion maggot (Fig. 13), feed on the roots, forming grooves all over its surface, which induces decay, and renders the roots unfit for use. In June they transform to pupa and to imagos, and are ready to make a new deposit of eggs. Hence we see why our early radishes are so very liable to attack, while later ones are often free from injury; though some years none seem to escape. Whether there are more than two broods a year, and whether they attack other plants than radishes, are, so far as I know, still open questions.
The late Dr. Walsh recommended hot water as fatal to these maggots, and harmless to the plants. I have tried this with some, though not satisfactory
Planting late, or planting on clayey soil, seems advantageous.
Dr. Fitch recommends wide distance between successive radish beds as beneficial. My own experience does not sustain this opinion. It is very desirable to find some application that will render the young plant obnoxious to the fly, thus preventing egg-laying, and yet be harmless to the plant. Who will discover such a compound? These same remarks will apply equally well to the onion and cabbage maggots.
Lytta cinerea, Fabr., and Lytta attrata, Fabr. Family, Meloida. Sub-Order, Coleoptera. These soft-shell, long-necked, trim beetles, the one ash-colored (Fig. 17, a),
the other coal-black (Fig. 17, b), are frequently very injurious to various vegetables and flowers. They sometimes attack beans and asters, and make quick work of whatever falls a prey to their voracious habits.
The larval condition of these beetles has been unknown or involved in doubt. It is supposed that they feed on the roots of grass and other plants.
The beetles appear in early summer and in autumn, and are very voracious feeders.
e male and female antennæ of b; d same of a
These beetles have the habit of falling off of the plants whenever the latter are suddenly jarred, so in case the plants are tall enough to receive a sheet beneath, or can be bent over an umbrella, the beetles may be readily gathered, and then destroyed by scalding or crushing.
THE STRIPED CUCUMBER BEETLE.
Diabrotica vittata, Fabr. Family, Chrysomelida. Sub-Order, Coleoptera.
This beautiful little beetle, yellow with black stripes (Fig. 18), which seems suddenly to fairly swarm on the cucumber and melon vines, is often the cause of great vexation to the gardener.
The larvæ (1, Fig. 18) feed on the roots and underground stems, mature in about a month, pupate in the ground, in which state FIG. 18. they continue about two weeks, when the imagos appear. There are two broods a year, and may be three. It passes the winter in the pupa state. The first imagos of the season attack the young vines, and in a single day may destroy them utterly. The later insects do not do so much damage, as the vines, from increased growth, are able to stand the attack.
Boxes covered with glass or millinet and placed L over the vines are sure protection, providing the beetles do not get inside. If glass is used, care must be taken to shade from the hot sunshine, or the plants may be ruined. These will form miniature hot-beds, and will hasten growth if rightly managed.
Paris green is a certain preventive, and in careful hands is harmless to the vines. I have used this remedy with the very best success. I would put one part green to six parts flour, apply when the vines. are dry, and add just as little as I could and see it on the vines. Add a little too much, and the vines are sure to be killed.
THE CODLING MOTH.
Carpocapsa pomonella. Linn. Family, Tortricidae. Sub-Order, Lepidoptera.
The little gray moths (Fig. 16, f and g) come forth in May and June, are
a work in apple: 6 place of entrance; d pupa; all the disgusting work narrated above, e larva; ƒ and g imagos; h head of larva; i co
except that the larvæ, upon leaving the apple, simply spin cocoons, in which they remain till spring, when they pupate; and in about two weeks the first moths appear.
The time when the first moths come forth varies from May 1 till July 1; so that moths will be issuing from May 1 till August 1, and the "worms" will be leaving the apples from the last of June till the fruit is gathered. My own experience seems to show that no pupæ are formed after the last week of August, as, so far as I have examined, all larvæ that leave the apple after that time simply spin a cocoon, in which they remain in larvæ till the next spring. Some of the observing fruit men of our State think that during the past season many of these insects pupated after that time. Such cases come not within my observation.
Of those larvæ which leave the apple while it still hangs in the tree, about one half crawl down, till beneath some bark or in some crevice they find seclusion in which to spin unobserved. Those which fall to the ground with the fruit crawl out; and if the ground is free from all rubbish, stumps, etc., they crawl up the tree and hide as before.
Place around the trunk of every bearing tree, midway between the ground and branches, a woolen cloth about five inches wide, and sufficiently long to pass around and lap enough to tack. This may be fastened with one or two tacks. I have usually found one placed in the middle to be quite sufficient. The tack should not be driven quite up to the head. Before the cloth band is adjusted the loose bark should be scraped off. This may be done earlier in the season, when time will best permit. The bands should be adjusted by June 20. Under these bands the "worms" will secrete themselves. By July 7 the bands around the earliest apple-trees should be unwound and examined, and