STRAWBERRY PESTS 



1949 



the Northwest. Otiorhynchus sulcatus oc- 

 curs about everywhere that 0. ovattcs is 

 found. In Oregon a larger species also oc- 

 curs (Fig. 3), which in the Milton-Free- 

 water district is doing considerable dam- 

 age in a few of the strawberry fields. In 

 the vicinity of Oswego, Oregon, a third 

 species, Otiorhynchus rugifrons (See Fig. 

 2), bids fair to outclass the Otiorhynchus 

 ovatus in its ability to multiply and to de- 

 stroy berry fields. 



Otiorhynchus sulcatus is not considered 

 of especial importance by the growers. It 

 apparently does not spread rapidly nor 

 multiply fast enough to injure a field to 

 a noticeable extent. The larger weevil 

 has a variety of host plants. It is cap- 

 able of injuring a strawberry patch by the 

 third season or the fourth spring from 

 planting. No especial study of these 

 species has so far been made. It would 

 seem that the same remedial measures 

 would apply as for ovatus. 



Strawberry Thrips. See Grain Thrips, 

 under Strawberry, 



Strawberry Weevil 



Anthonomus signatus Say 

 It is a curious fact, for which we have 

 no explanation thus far, that this insect 

 is not equally abundant in the same lo- 

 cality more than two or three years in 

 succession, and that after a period of 

 abundance there may be an equal period 

 during which nothing will be seen of it. 

 Meanwhile some other locality may be 

 suffering an invasion. Thus far we have 

 no way of predicting at the beginning of 

 a season whether or not injury will be 

 caused by the beetle. 



The strawberry weevil has been re- 

 ported from Virginia, Maryland, District 

 of Columbia and New Jersey. 



Life History, Habits and Iniury 



The adult beetle makes its appearance 

 in the strawberry fields as soon as the 

 season opens and growth begins. The 

 adult is less than an eighth of an inch 

 in length, black in color, with bands of 

 white scales, often with a reddish tinge 

 through the black ground, and with a 

 darker, bare spot on the side of each wing 

 cover behind the middle. 



This beetle hibernates in and under 

 leaves and rubbish, and mating takes 

 place as soon as the insects have fed. To 

 feed, before the blossoms open, the weevil 

 punctures a forming bud, usually select- 

 ing one that is well advanced, and thus 

 gets at the immature pollen. 



Eggs are laid in the buds of staminate 

 varieties only. The beetle first punctures 

 the bud with its beak as in feeding, then 

 turns, lays an egg into the puncture, turns 

 again, and with the beak forces the egg 

 into the bud, while the plant tissue closes 

 over the opening, leaving only a small dis- 

 colored spot. Then the beetle, shifting 

 its point of operation, crawls down the 

 stem below the bud about one-quarter of 

 an inch, and punctures this to such an 

 extent that the tissue is broken, the cir- 

 culation of sap arrested, and the further 

 growth of the bud checked. After a day 

 or two the bud wilts and droops, and in 

 a few days usually falls to the ground. 



As to the amount of injury, estimates 

 vary. All growers agree that it is seri- 

 ous, and it is not unusual to see 50 per 

 cent of the early buds cut. 



Since the beetles feed very little upon 

 exposed leaf tissue, spraying with internal 

 poisons is likely to have little effect How- 

 ever, Bordeaux has proven a fairly ef- 

 fective repellent. The mixture should be 

 4-4-50 formula. 



The spraying should be done just be- 

 fore blossoming begins, and should be 

 very thorough. Spraying while in bloom 

 is objectionable because of the danger 

 of preventing pollination by bees and 

 other insects. 



Another measure, sometimes resorted to 

 with good effect, is to burn over the field 

 just as soon as picking is done. The 

 vines are mowed close, left to dry out a 

 day or two, covered lightly with straw 

 and then set afire, when the wind is right. 

 This burns off all surface rubbish, the 

 field is cultivated, and the plants make 

 a new start. 



It has been demonstrated that the 

 plants can be kept free by covering the 

 rows with muslin or other light fabric, 

 put in place a week before the first buds 

 are ready to open, and that this covering 



