56 

 CHAPTER VII. 



MISCELLANEOUS INSECTS FEEDING ON FOLIAGE. 



Diabrotica soror — Remedies — Pear or cherrj' sing — Red mite or spider — Yellow mites — 

 Remedies for mites. 



THE CALIFOKNIA (12) SPOTTED DIABROTICA. 



Diabrotica Soror (Figure No. 43). Order, Coleoptera; Fam,., Chrysomelidee. 



The Diabrotica soror is a very close relation of the D. 12 punctata which 

 occurs in the East, and has often been mistaken for the same. Of all the 

 leaf beetles found in the State, none is more destructive in certain localities 

 and in certain seasons than this species. 



The imperfect engraving gives an idea of its appearance. The head is 

 black; the wing cases 3^ellowish green, with twelve distinct black spots. 

 Unfortunately, this insect is so common that it hardly needs to be de- 

 scribed. Being often associated with two or three species of ladybugs, it 

 is often thought by people to be one of them. A little closer examination 

 will reveal the fact that it has four joints in the toes, while a lady- 

 bug has only three. It is to be regretted that we still are in igno- 

 rance of the manner this insect hibernates. The mature insect' 

 is found rarely during the winter, and the presumption is that. _ 

 eggs are laid on grasses and other plants during the fall, and Fisme no. 43. 

 that the larva feed on the roots of plants. The Diabrotica is especially 

 bad near sandy watercourses and gravelly land, and its increase is always 

 favored by the cultivation of corn and other vegetables in the orchard. 



Eeine.dies. 

 It must be said that no verj' successful nor thorough remedy has been found for this 

 pest, and I can onlj' offer the partial remedies previously recommended; namely, spray- 

 ing with Professor "Riley's kerosene emulsion, but the spraying must be done early in the 

 morning, when the insects are sluggish. This remedy can only be used when the insects 

 appear early, while the fruit is still small. It will prevent the insects from destroying the 

 leaves. Later on, fumigation seems to be the only practical way of driving them from the 

 orchard. On the San Joaquin River, the striped squash bug (also a diabrotica) is kept at 

 bay by lighting smudge fires, on which a little wood tar is placed. This method will prob- 

 ably prove as efficacious against the spotted diabrotica. 



PEAR OR CHERRY SLUG. 



Selandria Cerasi. Order, Hymenoptera; Family, Tenthredinidse. 



This insect takes its name from the resemblance in the larval state to a 

 snail or slug. The parent is a small black fly, which deposits its egg on 

 the upper surface of leaves, where it can be seen as a small white speck. 

 The larva hatches from the egg in a few days, and commences to eat the 

 green part of the leaf, leaving only portions of the epidermis. When full 

 grown, it drops to the ground and transforms. Often three to four larva? 

 are found on the leaf. In such a case the leaf will be completely stripped, 

 and when trees are badly infested the influence will be felt next year, fruit 

 spurs being but imperfectly developed. 



Remedies. 

 When these insects appear later in the season, the throwing of dust with a shovel on 

 the tree, or better, air-slacked lime, is sufficient. But if they make their appearance early 

 in the season, spraying should be resorted to, that all the eggs may be killed. For this 

 purpose the sulphide of soda and soap wash is excellent. 



