1946 



ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



ragging it in a characteristic manner 

 (Fig. 1). The grubs feed on the entire 

 root system of the strawberry. The 

 smaller grubs are usually found feeding 

 on the fibrous rootlets, often devouring 

 them entirely or barking them so that 

 they die. A seriously infested plant may 

 be kicked out with the foot or easily 

 pulled up, often with the fibrous root 

 system eaten away. Undoubtedly a por- 

 tion of the grubs feed closely about the 

 main tap root and their feeding there 

 will sometimes girdle the crown. The 

 larger grubs are often found buried in 

 the tap root, and this food seems to give 

 them a more pinkish cast, giving rise to 

 a common belief that two species of lar- 

 vae are present. 



These beetles may be present in a patch 

 for years and but little injury result from 

 their attacks. In the weevil districts, un- 

 der normal conditions, an infested patch 

 will show a few sickly hills the first sea- 

 son, small patches here and there dead 

 the second season, and the patch rendered 

 worthless the next spring. This affords 

 one full crop in the usual system of cul- 

 ture. A condition that is becoming quite 

 common, however, is for the patch to be 

 materially weakened the first season; and 

 the second season, or the first expected to 

 yield a full crop, the patch is absolutely 

 worthless. Two factors render this condi- 

 tion possible. The soil is often already 

 infested with the grubs even though 

 strawberries have not been grown on the 

 ground previously, and again the beetles 

 from older infested beds all about tend 

 to concentrate on the new patch. 



Food Plants 



While the strawberry root weevil shows 

 a decided preference for the strawberry, it 

 is by no means confined to this food 

 plant. The following list is compiled 

 from reported food plants: 



Food Plant List for Adult Beetles of 

 0. ovatus 



Strawberry, raspberry, loganberry 

 blackberry, rose and other shrubbery, 

 borage, currant, muskmelon, sorrel (Rum- 

 ex acetosella) , wild rose, balsam root 

 (BalsamorrJiiza sagatata) , potatoes, wild 



buckwheat, hemlock, pumpkin, wheat, 

 corn, cabbage, cherry, red clover, apple 

 (fruit), dahlias (bloom), orchid (fruit). 



O t i 



Fig. 2. Strawberry Weevils. Upper figures, 

 adults of O. rugifons. Lower figures, adults 

 of O. ovatus. 



Food Plant List of Larvae — Root System 



Strawberry, raspberry, blackberry, 

 loganberry, wild strawberry, sorrel (Rum- 

 ex acetosella), grass (poa cerotine), tim- 

 othy, bluegrass, potentilla glandulosa, 

 June grass, white clover, hemlock, cab- 

 bage (?). 



Description 



The adult weevil is a snout beetle, 6 

 mm., or nearly one-fourth of an inch in 

 length. The color of the insect varies 

 from a dull reddish-brown when freshly 

 emerged to almost pitch black; the sur- 

 face is roughly pitted and slightly shiny. 

 The beak is short, broad and emarginate 

 at the tip; there is a distinct puncture 

 between the eyes. The antennae are el- 

 bowed and consist of nine segments. 



The Egg 

 Very small, milky white, smooth and 

 translucent at first but later yellowish- 

 brown and rough. 



Larvae 



Pinkish or white and when full grown 

 three-eighths inch long. On each segment 

 is a row of reddish-brown hairs. 



Pupa 



Pure white at first but turning to dark 

 brown finally. Segments of head, thorax 



