INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



391 



grown caterpillars are very hairy, yellowish or greenish in color, with 

 a darker stripe along the back and a yellow stripe along each side. 

 The body is covered with whitish hairs, which arise from black and 

 orange-yellow tubercles. 



Life History. — This species hibernates in the pupal stage within a 

 cocoon attached to tree trunks, fences, rubbish or under the ground. 

 The moths emerge in the spring, mate 

 and, during the nights, the females 

 deposit from four hundred to five 

 hundred eggs in clusters upon the 

 leaves of the food plants. The cater- 

 pillars feed in colonies and spin webs 

 large enough to accommodate all the 

 members. The web may embrace a 

 large limb of a tree. When full- 

 grown the larvae leave the web and 

 descend to suitable pupal quarters. 

 There are two broods a year, the sec- 

 ond appearing late in the summer. 



Nature of Work. — The larvae feed 

 upon the foliage, inclosing their par- 

 ticular feeding places in large webs 

 or tents for protection. 



Distribution. — This introduced 

 pest is common throughout the Sac- 

 ramento and San Joaquin valleys and 

 is the web-worm most often encoun- 

 tered. 



Food Plants. — The spotless fall 

 web-worm feeds upon the foliage of a 

 great number of wild and ornamental 

 trees and shrubs, as well as upon 

 fruit trees. During the year 1912 

 much damage was done to willows in 

 the San Joaquin Valley, while peach 

 trees suffered in Sutter County. 



C o n t r o 1. — The application of 

 arsenical sprays, the collecting of the cocoons and the burning of the 

 nests or webs containing the lame with a torch are the remedies 

 usually recommended for this pest. 



Natural Enemies. — Internal parasites probably play an important 

 part in the control of this moth. 



Fig. 391. — Adult female and male 

 of the fall web-worm. Hi/phantria 

 ciaiea (Drury), «t the top and female 

 and male of the spotless fall web- 

 worm, Hyphantrki textor Harris, at 

 the bottom. Natural size. (Orig- 

 inal) 



NOCTUID^: (Family) 



ARMYWORMS AND CUTWORMS 



General Life History.— The adult members of this family are prac- 

 tically all night-flyers. The caterpillars of many are known as cut- 

 worms and armyworms and are among the most destructive insed 

 pests. In great numbers they often advance from field to field like 



