STRAWBERRY CROWN GIRDLER. Otiorhynchus

ovatus, Linn.

EDITH M. PATCH.

More than a little annoyance has been caused in the State by the strawberry crown girdler, a small, black, snout beetle, noticed in some localities especially for its habit of crowding into the house.

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It was the protests of tried housekeepers that drew attention to the beetle last season. We have been overrun with these hateful pests." "I killed more than 400 one evening in the front room." "They travel all over the house and crawl from baseboard to ceiling only to drop to the carpet and try it over and over again. They hide under any protection, carpet, clothing, bedding, and are a general nuisance." Such reports came from Maysville Center, Houlton, Monson, North Wayne and Caribou during September, June and August. They seemed worthy of some attention and this season observations of the strawberry crown girdler were made with reference to the habit of crowding into houses, habits of larva and adult, and remedial or protective measures.

The beetles in the house with reference to their out-of-door habits. The troublesome habit this beetle has of crowding into the house and getting into the way makes it an objectionable insect, although it does no real harm indoors. It feeds upon plants and is therefore, unlike the larder and carpet beetles, interested neither in the food supply of the household nor in clothing and carpets. For the past two years the beetles have occurred in great numbers about the first of June, lasting through that month, and have appeared again in August and September. The house which seems to be troubled most at North Wayne was built in 1822, and as might be expected had crevices near the foundation which offer attractions for insects in search of a hiding place. The beetles were most numerous

in the front room into which they crept through cracks near the base boards, though they entered the house also at the doorway under the screen. If they were content to be quiet after once finding a hiding place, their presence would be less objectionable, often unsuspected indeed, but their exasperating persistence in climbing over everything only to drop into everything else" as one housekeeper complained, entitles them to the rank of household pests.

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The house at North Wayne was not visited until June 27, 1905, and at this time the beetles were not numerous enough to give sufficient data as to the relation of their house infesting habits to their out-of-door movements. Farther north, however, near Houlton July 5, ample opportunity for observation was afforded. A day's search was made for the adult beetles out of doors. They were not found hiding under planks, stones or other objects in damp places, but in dry soil they were frequently dug up from among the roots of plants. Some of these were newly transformed from the pupal condition and would naturally be found under the surface where the larval period was passed, but others were well hardened specimens which seemed to have sought the roots from above ground, very likely for the deposition of eggs.

Toward the top of a hill along a hot, dusty road more of the beetles were found during the day than elsewhere. The road was bordered by white clover, which may have been significant, for larvæ of the beetles were found at the roots of this plant. The puzzling thing about the beetles here was the fact that they (ordinarily more active during the evening) were wandering restlessly across the road at mid day, under a scorching sun which they were evidently glad to avoid, for every time a leaf or chip was placed near these wanderers they crept underneath and remained there. The question why, if they wanted shelter, they had not apparently found it before mid day, was unsolved until a horse and carriage passed, scattering dry layers of clay with which the road was well supplied at this place. Then disturbed beetles were seen everywhere poking out from crumbled clay bits and walking off in search of another nook in which to finish their nap. More than 200 beetles were captured easily after this disturbance before they had found satisfactory

hiding places. Except when the beetles were moving it was difficult to see them, for though they are black they were too thoroughly dust covered to be detected readily in the roadway.

Toward dusk the hill top road was again visited and this time the beetles were more numerous and more interested in their journey, for they had voluntarily quitted shelter, and were out for purposes of their own. Before dark, beetles were seen everywhere along places where they had been sought in vain during the day; fence rails, piles of sun heated stones, tree trunks, sides of sheds, came in for their share of the active beetles as well as doorway and window sill by which the creatures were entering the house.

These out-of-door observations lead logically enough, it seems, to the conclusion that the house seeking habit of the strawberry crown girdler is merely an incident in the general trend of the movements of this beetle,—perhaps accident would be a more appropriate term from the beetle's standpoint for the house proves a gigantic trap from which the beetles, in spite of restless and persistent climbing, find no means of egress. Like the old fashioned wire fly traps, the house is easier to enter from the foundation than to get out of at the ceiling. The beetles desire a dry shelter and find a building as acceptable as a clump of clay,—until they try to get out.

The restless wanderings of these beetles in and out of the house is probably a necessary impulse for the spread of the species for, unlike many insects, they are incapable of flight and are doomed to walk the earth if the succeeding generations are to find new feeding grounds.

It may not be entirely without interest to question whether the presence of these beetles in houses is augmented by lights as is frequently the case with insects most active at night. At North Wayne the room most troubled was the closed front room where no lights were taken during the evening except for a little while to collect the beetles. Yet in one evening over 400 were killed in this room.

The foregoing discussion has a bearing upon two characteristics commonly accredited this beetle. It is spoken of as gregarious," and its entrance into houses has been explained as "hibernating."

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Certainly these beetles were not observed to show gregarious instincts in the sense of seeking the companionship of others of their kind, but wander about quite indifferent to the direction or destination of their kindred. Of course in places of concentrated local infestation many beetles independently happen upon the same shelter.

If the beetles were found in houses only in the fall their presence might seem a hibernation, but in Maine there are two times when they appear most abundantly,—during June and in August and September, and the June lot are as troublesome in the house as the fall beetles. These two marked periods might seem to indicate two annual broods, but it is difficult to obtain dependable evidence with an insect which is to be found as adults, pupæ and larvæ of various sizes, from early June until fall, as is the case with this beetle in Maine.

Feeding habits of larva. At North Wayne, late in June, a day was spent in search of larvæ of the strawberry crown girdler. Close to the foundation of the house near the room most troubled by the adults, the roots of a grass, Poa cerotine, were found to be freely infested by nearly grown larvæ, and this grass had doubtless supplied a fair proportion of the troublesome beetles. A few pupa and some newly developed adults, still brown in color, were found among the roots with the larvæ. The main seat of action, however, seemed to be the strawberry bed. The weather had been wet and cold for some time, but in spite of that there were conspicuous wilty places in the bed, here and there. The strawberry plants in these spots could be lifted from the ground with the slightest pull, for their roots were eaten through at a distance of two or three inches from the crown. The appropriateness of the popular name of this beetle was thus approved for the strawberry crowns in this bed were certainly girdled."

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A space containing three square feet was selected at random. from one of the wilted places in the bed. More than 200 nearly grown grubs, pupæ, and freshly developed adults of the girdler were found about the strawberry roots in this space, besides which there were one young cut worm and four Lachnosterna grubs under half size. How many more there would have been if eight fat predaceous ground beetles had not been skirmishing

through these three square feet of infested soil is a question, depending for its solution upon the capacity of the beetles. It was not surprising to learn, one month later (July 28) that this strawberry bed was more than half dead.

Near Houlton on the place where the beetles were most annoying there was no strawberry bed, and a day was spent examining the roots of meadow plants, July 6, 1905. Larvæ and pupæ of the girdler were found at the roots of wild strawberry, Timothy grass, June grass and white clover. Large potato fields were close at hand, but no signs of the crown girdler were found about potato vines which were dug up in various places in the field.

Feeding experiments with adult beetles. Several hundred beetles taken near Houlton early in July were brought to the laboratory for the purpose of testing the range of their food plants. These were confined for three days at a time in bottles containing perfect leaves. The following list records such leaves (or flowers as indicated) as were found to be eaten to a greater or less extent during this time: Apple, cauliflower, red clover (blossom), red clover, woodbine, Tartarian honeysuckle, turnip, radish, white clover (blossom), white clover, rose (petal), oak, dandelion, lettuce, maple leaf, lawn grass, sorrel, timothy grass, basswood, raspberry, mulberry, spirea, currant, strawberry, rose, plantain, celery, mountain ash, Roman wormwood, rhubarb, bean, nasturtium, wolf weed, nightshade, box elder, thistle, cottonwood, elm, geranium, flowering currant, dahlia, syringa, peony, blackberry, fall dandelion, asparagus, horse radish, pea, chickweed, wild cherry, gooseberry, birch, iris, willow, "self heal."

While it is probable that beetles placed in confinement would eat some leaves which in the open they would avoid for other food, still the foregoing test bears out the reputation of this insect as a general feeder.

REMEDIAL MEASURES.

Arsenate of lead. Two experiments were made with elm leaves (a favorite diet of the girdler) dipped in arsenate of lead, mixed at the rate of 4 pounds to 50 gallons of water. For the first, 42 well fed beetles were confined with a few poisoned leaves for two days, when 18 were dead and 24 still alive. For the second