38 



THE MONTHLY BULLETIN. 



The life history of the peach twig borer is in brief as follows : The 

 insect passes the winter in minute burrows made in the bark and located 

 principally in the crotches of the limbs. Tiny silken tubes, covered with 

 chewed bark, project upwards from the burrows, and the extent of the 

 infestation can be determined by the number of these tubes. In the 

 early spring the larvae come out to feed on the tender shoots. They 

 become full grown about May, passing the resting stage in crotches in 

 the bark. The adults emerge about one week after pupation. 



The use of a commercial preparation of lime-sulphur, diluted one 

 part to ten parts of water, just before the buds are opening, will give 



Fig. 21. — Apples disfigrired by the attacks of the 

 purple apple aphis when the fruit was young. 

 Tliese were picked at harvest time. Reduced one- 

 half. (After Essig, Injurious and Beneficial Insects 

 of Cal. Supplement to the Mo. Bui. Cal. Hort. 

 Oornm., Vol. IV, No. 4.) 



excellent result.s. This solutioii already prepared can be obtained from 

 the various insecticide dealers. This spray will not only control the 

 twig borer, but also peaeh leaf curl, and several other diseases. 



The Purple and the Green Aphides. 



Two important plant lice working upon young apple shoots are the 

 purple and the green aphides. The young fruits are discolored and the 

 leaves curled by the attack of these lice. The former species causes the 

 fruit to assume all sorts of abnormal shapes as well as checking its 

 growth so that it does not attain to commercial size. The winter is 

 passed in the egg stage, and eggs being deposited on twigs in the fall. 

 P. R. Jones,* in a preliminary report on spraying the eggs of these 



♦Monthly Bulletin, Cal. Hort. Comm., Vol. 4. No. 1, page 2 0. - 



