West Virginia Agricultural and Forestry Experiment Davis College of Agriculture, Natural Resources Station Bulletins And Design 1-1-1909 The Grapecane Gall-Maker and the Grapecane Girdler Fred E. Brooks Follow this and additional works at: https://researchrepository.wvu.edu/ wv_agricultural_and_forestry_experiment_station_bulletins Digital Commons Citation Brooks, Fred E., "The Grapecane Gall-Maker and the Grapecane Girdler" (1909). West Virginia Agricultural and Forestry Experiment Station Bulletins. 119. https://researchrepository.wvu.edu/wv_agricultural_and_forestry_experiment_station_bulletins/119 This Bulletin is brought to you for free and open access by the Davis College of Agriculture, Natural Resources And Design at The Research Repository @ WVU. It has been accepted for inclusion in West Virginia Agricultural and Forestry Experiment Station Bulletins by an authorized administrator of The Research Repository @ WVU. For more information, please contact [email protected]. WEST VIRGINIA UNIVERSITY AGRICULTURAL EXPERIMENT STATION MORGANTOWN, W. VA. Bulletin 119. January, 1909. The Grapecane Gall-Maker and the Grapecane Girdler. By FRED E. BROOKS. [The Bulletins and Reports of this Station will be mailed free to anj citizen of West Virginia upon written application. Address Director of Agricultural Experlpient Station, Morgantown, W. Va.l . REGENTS OF THE WEST VIRGINIA UNIVERSITY Name of Regent P. O. Address Hon. C. M. Babe Falls, W. Va. Parkersburg, Va. Hon. J. B. Finluy W. Hon. D. C. GaIvIvAhdr Charleston, W. Va. Hon. E. M. Grant Morgantown, W. Va. Hon. C. E. Haworth Huntington, W. Va. Hon. C. p. McNell Wheeling, W. Va. Hon. L. J. WiLUAMS Lewisburg, W. Va Hon. T. p. Jacobs New Martinsville, W. Va. Hon. J. R. Trotter Buckhannon, W. Va. President of the Board of Regents C. M. Babe President of the University D. B. Purinton Treasurer A. R. WhiTEHill Auditor W. J. White STATION STAFF James H. Stewart, A. M Director and Agriculturist Bert H. Hite, M. S Vice Director and Chemist W. M. MuNsoN, Ph. D Horticulturist W. E. RuMSEY, B. S. Agr Entomologist Mahum James Giddings, B. S Bacteriologist Horace Atwood, M. S. Agr Assistant Agriculturist Fred E. Brooks Associate Entomologist Frank B. Kunst, A. B Assistant Chemist Chas. E. Weakley, Jr Assistant Chemist J. H. Berghuis Krak Assistant Chemist A. L. Dacy, B. So Assistant Horticulturist W. J. White Bookkeeper M. A. Stewart Librarian Alice EnglE Stenographer B. D. White. Herdsman Twm. F. Tmbach. Greenhouseman The Grapecane Gall-Maker and the Grapecane Girdler. INTRODUCTION. We have in West Virginia two species of little snout-beetles that injure grapevines by attacking the new canes soon after growth begins in the spring. They are the grapecane gall-maker, Ampeloglypter sesostris Lee. and the grapecane girdler, Ampel- oglypter ater Lee. As' their generic name indicates, the two species are nearly related. So . far as size and shape are con- cerned, the differences are scarcely discernible, but in color the gall-maker is dark brown, while the girdler i*s shining black. Their methods of attacking the vine are also distinct. The gall- maker, in providing a place to deposit its egg, makes a wound in the cane which develops later into a gall-like swelling, whereas the girdler, in its egg-laying operation, cuts off the tip and otherwise mutilates the end of the young cane. Both insects vary greatly as to their abundance in different seasons. For a year or two the characteristic marks of one or both species will be very conspicuous on the vines, and then for a period of a few years following they may be almost entirely absent. This irregularity in their occurrence is due largely to the fact that when the beetles increase in numbers there follows a corresponding increase in the numbers of their natural ene- mies. These enemies, which are chiefly parasitic insects, attack the beetles in their immature stages and sometimes reduce them almost to the point of extermination. When there comes a de- crease in the parasites the beetles begin to multiply, but since the females of neither species produce many eggs it takes them some time to recover from the set-back. Very little preference is shown by either insect for any par- 322 ticular species or variety of grape. I have found the evidences of their work on about twenty varieties of cultivated grapes and on the three wild sorts that are commonly found in the woods and grown-up fields of the northern and central portions of this state. These wild sorts are the northern fox grape, Vitis lahrusca, the "hill-grape" or "frost-grape," Vitis aestivalis, and the "chicken grape," or "pigeon grape," Vitis cordifolia. Both the <2:all-maker and the girdler are undoubtedly natives of this coun- iry and must have confined their attacks originally to wild grapes and kindred plants. Digitized by the Internet Archive in 2010 with funding from Lyrasis IVIembers and Sloan Foundation http://www.archive.org/details/grapecanegallmak119broo The Grapecane Gall-maker, a, egg; b, larva; c, pupa; d, adult; e, beetle making the wound in the cane that contains the egg and later causes the gall to form; f, transverse section of wound showing egg in lower chamber. All except "f" greatly enlarged. Drawings by A. B. Brooks. The Grapecane, Gall-Maker. Ampeloglypter scsostris Lee. Order Coleoptera ; family Curciilionid?" HISTORY AND DISTRIBUTION. About ten years ago this insect was made the subject of an investigation in Ohio, conducted by F. M. Webster, and the results were published as Bulletin ii6 of the Ohio Experiment Station. The bulletin gives the more essential facts in regard to the gall-maker and its habits, but since the publication of that paper a few additional points relative to the species have been observed in West Virginia. These observations, together with those already published, give us a fairly complete knowl- edge of the insect as it occurs in this section of the United States. Webster collected galls from grapecanes in June and kept them until the larvae which inhabited them transformed to beetles in August and September, thus showing that the adult stage is reached in late summer instead of in the spring;, as had been supposed previously. I was unable to duplicate this breeding work satisfactorily on account of the extent to which my specimens were parasitized. On the other hand, I watched the female on several occasions while she was engaged in egg-laying, an operation which I believe has not been de- scribed heretofore. Most of my observations on this species were made at French creek, W. Va., in the summer of 1905. where, at that time, the beetles were very abundant. Since 1905 but few specimens have been seen in that locality and examples of their work have been correspondingly scarce. The species was described by LeConte in 1876, from speci- . 324 mens collected in Missouri. Since that time it has been reported from Minnesota, Ohio, Pennsylvania and other eastern, south- eastern and mid-western states. THE ADULT INSECT. The gall-maker in its adult stage is a reddish-brown beetle which measures about one-eighth of an inch in length and one- twentieth of an inch in width. It has a curved snout, one-third as long as the body, which it carries projecting forward and downward. The thorax and head are finely and densely punc- tured and the wing-covers are furrowed longitudinally. The beetles appear on grapevines during the month of May and are present for several weeks. They are so small, however, that they rarely attract attention. Soon after their appearance the females begin to oviposit in the young canes, and after the eggs are laid the parent beetles of both sexes disappear in late June or July. The beetles feed sparingly on the vine and in doing so make little pits in the young tendrils, in the buds and bark on new canes and in the mid-ribs on the underside of leaves. It is probable also that the female swallows some of the tissue which she tears from the cane in making her egg-chamber. The injury which results from the pits eaten in the plant is insignificant, but the manner of feeding is otherwise of some interest, since it indicates that the beetles may be killed with arsenical sprays. The beetles are active only during warm days. In cool or rainy weather and at night they hide beneath the strips of bark adhering to old canes, or remain motionless on the underside of the leaves. APPEARANCE OE INJURED VINES. The injury done to the vines by this insect is in the shape of gall-like growths that begin to develop on the new canes early in the summer. These galls are abrupt swellings of the Photographs showing injury done by the Grapecane Gall-maker, a, a, newly made wounds; b, larva feeding in the cane and the gall beginning to form; c, c, fully developed gal^s. Natural size. 325 cane to something like twice its normal diameter, the enlarge- ments being an inch or an inch and a half in length. The swell- ing is about uniform around the cane except that on one side there is a deep longitudinal scar from a half to three-fourths of an inch in length. This scar comes from a wound made by the female beetle in preparing a place to lay her egg. The gall is almost invariably located just above a joint of the cane. I examined several hundred of the galls and found only one in which the lower end was as much as an inch above a joint. The one exception was that of a gall located three- fourths of an inch below a joint. The cane on which this gall was found w^as being trained in a horizontal position and the gall occurred just below instead of just above the joint, evidently through an error on the part of the beetle that made the wound which caused the gall to form.