THE MONTHLY BULLETIN. 9 



THE CITRUS RED SPIDER. 



Tctran.i/chus inytllaspidis Riley. 

 (Fig. 11.) 



General Appearance. — The adult insects are cardinal red and 

 scarcelj^ larger than a pin point. They often occnr so abundantly as to 

 give the fruit and foliage a red color. The eggs are globular and red, 

 as are also the younger stages. 



Life History. — The eggs are suspended upon minute stalks with 

 guy webs as supports. They hatch in from nine to twelve days, being 

 laid from ]\Iay on throughout the warm summer months. The first 

 born are six-legged l)ut after the first molt acquire another pair, making 

 the usual number. In two weeks they are full grown and begin egg 



Fig. 11. — The citru.s red spider, Tetrnni/chus nii/tilaspidis Riley. Much enlarged. 

 (After Volck. Courtesy Cal. Exp. Sta.) 



laying. They live from thirty to thirty-five days, thus making the life 

 cycle cover a period of about six weeks. By far the greater numbers 

 occur during the warm summer months when most of the damage is 

 done, but great damage often occurs until late in winter. On deciduous 

 fruit trees the eggs are deposited at the bases of the last year's shoots 

 and do not hatch until the following spring. 



Distribution. — Occurs throughout most of the State, but is particu- 

 larly destructive in the southern citrus-growing sections. 



Food Plants. — Primarily a citrus pest, working uniformly upon the 

 foliage and fruit. Other food plants are as follows : apple, prune, 

 peach. 



Control. — The first methods of control consisted in the application 

 of dry flowers of sulphur thrown upon the tree by hand. Later power 

 blowers were employed and these are still used, but to the sulphur is 



