INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA; 



405 



Food Plants. — The valley oak {Quercus lobata), the coast live oak 

 (Q. agrifolia), maul oak, black oak, cork oak and various other oaks 

 are attacked. 



Control. — Due to the large size 

 and great numbers of the in- 

 fested trees, there seems to be a 

 feeling that successful control 

 measures, can not be employed. 

 However, it has been demon- 

 strated that the trees can lie 

 sprayed very easily with a good 

 power sprayer and a woodland 

 or ordinary nozzle and the pes' 

 successfully controlled. Lead 

 arsenate, 4 to 5 pounds to 50 gal- 

 lons of water, is recommended in 

 I he winter, as soon as the eggs 

 begin 1o ha+ch. A second spray- 

 ing should follow if the caterpil- 

 lars become serious or if a large 

 second brood appears in July or 

 August. One spraying, however, 

 is usually sufficient. 



Nature! Enemies. — Internal 

 hymenopterous parasites play an 

 important part in the control of 

 this moth under certain condi- 

 tions, but they do not seem to be 

 able to cope with it under all circumstances, as shown in the last two 

 years. A large yellow and black chalcid appears to he the most 

 numerous. Pimpla h<hr< nilsii Cr.'-"" and P. conquisitor Say 292 also prev 

 upon it. 



Fig-, ion. — Adults o" the California oak 

 moth, Phryganidia califarnicft Pack. Fe- 

 male at top and male ;it bottom. Nat- 

 ural size. (Photo by Leroy Childs) 



THE YELLOW-NECKED APPLE CATERPILLAR 

 Datana ministra Drury (Family Notodontidse ) 



(Fig-. 409) 



Description. — The moths are dark brown and have a wing expanse 

 of from If to 2 inches. The front wings arc cinnamon-brown with 

 three or four darker lines across each, while the hind wings arc pale 

 yellowish without markings. The eggs are ovate, white and deposited 

 in clusters on the undersides of the leaves. The young caterpillars 

 are dark brown with black somewhat obscure stripes. When full- 

 grown they are 2 inches long and striped longitudinally black and 

 yellow. The first body segment behind the head is yellow or orange- 

 colored, which gives rise to the common name. The body is clothed 

 with long, fine whitish hairs. When disturbed the head and tail are 

 thrown into the air, the body being supported only by middle prolegs. 

 The pupte are dark brown and less than 1 inch long. 



29 'Doane, R. W.. Jr. Be. But. V.. p. 346, 1912. 



-■'-Insect Life. III. p. 462, 1890. 



