INSECTS

INJURIOUS TO THE FARMER AND GARDENER ·

A SERIES OF ESSAYS, BY WILLIS GAYLORD.

Or all the departments of Natural Science, there is perhaps none that possesses so much practical interest to the agriculturist as ENTOMOLOGY, or that part of it which relates to the character, transformation and habits of Insects. The farmer may remedy almost every other disadvantage, and secure almost every advantage, either by change of location or improvement in culture; but no such change or improvement can reach the great evil of insects, except in the most partial manner. They surround him every where-they spring up at every step. Each plant introduced into cultivation introduces new enemies, and if, as is asserted by an eminent British Entomologist, every plant is preyed upon in its several parts of roots, stems, leaves and seeds, by as many as five or six different species of insects, we may readily conceive what a host of these depredators the labors of the husbandman assist in feeding. It may safely be affirmed that insects cause more loss to the farmers of the United States, destroy more of their crops, and cause greater deductions from their profits, than all other animals combined, and perhaps more than all other causes united. From the time the seed is put into the ground till the ripened seed is in the garner, there is a continued succession of attacks; and experience in a large part of our Union shows that whenever so deposited, it is very far from being safe from these feeble but still powerful depredators on the products of

man's labor and skill.

Insects are the more injurious because their insignificance serves in part as a protection, and as a general rule it will be found that the smaller and more despicable the individuals of any tribe of insects may be, these things will be fully compensated by their greater numbers, activity and voracity. Were the facts not such as are daily or hourly observed, the amount of injury such minute animals can inflict, would be incredible. A thousand lions let loose in our country would not occasion so much loss of property as does the canker-worm in a single season; nor would the march of a herd of mammoths over the western prairies leave such ruin behind as the march of the army worm.

In

sects so minute and frail as to require a glass for their examination, or the most careful handling to prevent annihilation, by their numbers destroy the hopes of the farmer, and convert the fruitful fields into a desert. It requires no argument to prove that animals capable of producing such effects, whatever may be their insignificance individually, are deserving careful attention; and if any means of arresting their multiplication or preventing their ravages can be discovered, they should be made known. In entering upon a notice of some of the insects most injurious to agriculture, it is believed a short account of insects, as such, may be useful, as it is evident some introductory knowledge is necessary, that the observer may not make mistakes in the proper position of the depredator he is pursuing or has discovered. In doing this, all technicalities will as far as possible be avoided—the trivial or common, as well as the scientific names when known, will be given, and the whole made as practical as possible. All insects may be classed as follows:

1. COLEOPTERA. This order includes all the kinds commonly called beetles. Their wing cases are hard, of various colors, and protect the true wings from injury.

2. ORTHOPTERA. Crickets, grasshoppers, locusts, &c., belong to this order of insects.

3. HEMIPTERA. This order includes the froghoppers, bugs, aphides, &c. The name means half-wings.

4. NEUROPTERA. sentatives of this order.

The libellulæ or dragon flies are good repre

5. HYMENOPTERA. The ichneumon fly, hornets, bees, &c., belong to this order.

6. LEPIDOPTERA. All butterflies and moths are included in this order of insects.

7. STREPSIPTERA. The parasitical insects found on wasps and bees, belong to this order.

8. DIPTERA. The horse, cattle, and house flies, are representatives of this order.

9. SUCTORIA.

The flea is the most common insect of this order. 10. PARASITA. The louse found on man, and those on birds and animals, represent this order.

Such distinctions may seem unnecessary, but the value of observations on the habits of insects mainly depends on the descriptions being such that there may be no mistake as to the animal itself when seen by others. To mention only one instance, the words bug and beetle are

used by many as synonymous, but the above distinctions will show tha the beetles have hard wing cases, while bugs proper have only the rudiments of wings or half wings. That destructive insect, the wheat weevil, by some has been confounded with the wheat fly; and much. useless discussion has taken place that might have been spared had it been recollected or known that the true weevil is always a bug or beetle, while the fly frequently mistaken for it is a true fly, belonging to the Dipterous instead of the Coleopterous order.

The metamorphoses, or changes that insects undergo, are among the most curious things in the whole range of animal existence; and the nature of these changes should be understood, or mistakes as to the identity of insects can scarcely fail of occurring. That most insects are produced from eggs, people are aware; but how many even now are ignorant that from the common wriggler of our cisterns of rain water, proceeds the musquito; from the hairy caterpillar of autumn the beautiful tiger moth; or from the stinking, odious fennel or carraway worm, one of the most splendid of butterflies. Mr. Kirby states the curious fact that the Greek word from which our word metamorphosis is derived, is not found in any Greek writer previous to the date of the New Testament, and its use in natural science seems to have been derived from its mythological signification.

There has been some discordance as to the mode of the successive developments of insects, but it is enough for the present purpose that we know of their existence in the states of the egg, the larvæ, the pupa or chrysalis, and the image or perfect insect. Some few, however, do not pass through these several transformations; but issue from the egg nearly in the form they are to maintain through life. The apterous insects or those without wings, such as the ant, are mostly of this class.

The stage of life in which the insect becomes of interest to the agriculturist, is the larva or worm stage, as it is in this that they usually continue the longest, and effect the greatest mischief. In this state they eat voraciously, and generally increase in size rapidly. Of this the common flesh-maggot and silkworm furnish familiar examples. At the termination of the larvæ state, the insect frequently sheds its former covering, becomes motionless, and in this state is called the pupa. After remaining in this condition for a longer or shorter time, the shell or covering of the pupa cracks, and the perfect insect issues, to enjoy for a few days its new life, propagate its species, and die. Comparatively little damage is done to the farmer by insects in the perfect state, though there are some exceptions, as in the case of lo

custs, grasshoppers, etc., but the damage they effect by their voraciousness in the larvæ state is immense., The egg of the insect is generally deposited on or near the spot where the future insect is to find its subsistence, and after a short time is hatched, or the larvæ issues from it to commence its depredations; but in a few instances, the. egg is hatched in the body of the parent, and is active immediately on expulsion. The larvae of the grey flesh-fly is an instance of this ovoviviparous production. In some few cases, the instinct which guides the female insect in depositing its eggs where the young will find food, fails her, and the young consequently perish. A curious example of this occurs with the flesh-fly Musca carnaria, which we have known mistake that fetid mushroom, the Phallus canis, for carrion, and deposit great numbers of eggs upon it, where they were sure to perish in a few days.

In treating of the insects injurious to Agriculture, it will be more convenient perhaps, to divide them into the following classes: those injurious to the Vegetable Garden; those injurious to Field Crops; those injurious to Orchards and Fruit Trees generally; and those injurious to Domestic Animals.

SECTION 1. Insects injurious to the Vegetable Garden.

Of the multitude of insects that infest our gardens, there is, perhaps, none more common or destructive than the cut worm. This is the larvæ of a moth, which is very well described by Mr. Bruce, in the first volume of the American Journal of Science, under the name of Phalana noctua devastator. The worm is brown, fat and sluggish, generally about an inch in length, and feeds only at night. Cabbages, beans, etc., are its favorite food. These it cuts off at the surface of the ground, feeds on them until it is gorged with food, when it burrows in the ground near its place of feeding, and where it may be easily found and killed. There are quite a number of different worms known by the names of cut worm, black grub, etc.; but as their habits are nearly the same, and are destructive, for all useful purposes they may be classed together. Dr. Harris, a few years ago, collected a quantity of cut worms from the vegetable garden, the corn field and the flower garden, all as he supposed of the same kind; but when they came to produce the perfect insect, as many of them did, the collection produced no less than five different species of moths. From the fact that fields or gardens ploughed in the fall are not as liable to suffer