ORANGE PESTS 



1497 



Orange Maggot 



Trypeta ludens Loew 



This is an insect that is a serious pest 

 of oranges .in Mexico. The larva or mag- 

 got develops within the fruit similar to 

 the codling moth within the apple. From 

 four or five to 15 or 20 of these maggots 

 may occur in a single orange. The eggs 

 from which these maggots hatch are de- 

 posited on the fruit. About 70 eggs are 

 laid by a single fly, and these are dis- 

 tributed over from eiglit to a dozen 

 oranges. When the worm has attained its 

 growth it leaves the fruit, which usually 

 falls. In case it does not fall, the mag- 

 gots drop to the ground. The complete 

 life cycle requires about three months. 



Appearance of the Orange Maggot 



The larva or maggot is dirty white in 

 color and when mature measures slightly 

 less than one-half of an inch long. This 

 is the stage of the insect that occurs in 

 the pulp of the orange. The puparium, 

 which is the next stage, is light brown in 

 color, barrel-shaped and measures about 

 one-third of an inch long. The adult fly 

 is straw yellow in general color with 

 brownish markings on the wings, which 

 when spread measure about five-sixths of 

 an inch across. 



H. J. QUAVI.E. 

 Califoi'nia Expei'iment Station Bulletin 214. 



Orange Tortrix 



Tortrix citrana Fern 



(Family Tortricidae) 



General Appearance 

 The adult insects are gray in color and 

 hardl.v one-h;ilf inch long. The eggs are 

 cream-colored, circular, flat and covered 

 with fine mosiac-like markings. They are 

 laid so as to overlap like the scales of 

 a fish. The larvae when full grown vary 

 from one-half to three-quarters of an inch 

 in length and are white or dusky in color. 

 The chrysalids are brown. 



Life History 



The eggs are laid in clusters in early 

 spring, usually upon the undersides of 

 the leaves, each moth depositing about .50. 

 The larvae hatch in about two weeks and 

 feed upon the surface of the orange fruit 



or upon the foliage or tips of the shoots 

 of the other hosts. Burrows are also 

 made in the fruit, especially through- 

 out the peel, thus causing decay and ruin. 

 The young reach maturity in about two 

 months. The pupal stage is passed with- 

 in the old burrow or any protected place 

 outside. The adults emerge in from one 

 to two weeks. The broods overlap, but 

 there are probably three generations a 

 year. 



Food Plants 



The greatest damage is done to the 

 fruit of the orange, by making burrows 

 throughout the peel and often into the 

 pulp. 



Control 



Though the destructiveness to oranges 

 has been quite great in a few instances, 

 yet not enough actual damage has been 

 done to warrant the application of poison 

 sprays or other methods necessary for 

 control. The parasitic braconids which 

 work upon the larvae no doubt play some 

 part in the subjection of the pest. 



Natural Enemies 



The tachina fly (Phorocera parva 

 Bigot) and the internal braconid para- 

 sites. 



Purple Scale 



Lepidosaplies beckii Newm. 

 General Appearance 



The female scales are elongated, oyster- 

 shaped, varying from onersixteenth to 

 one-eighth of an inch in length and one- 

 third as wide. The male scales are much 

 smaller than the females. The scale or 

 covering varies from a reddish brown to 

 a rich purple color, giving rise to the 

 name. 



Life History 



The pearly white eggs are laid in the 

 large sac under the protecting scale. 

 From these are hatched males and 

 females, which mature in from four to 

 six months. The fruit, limbs and foliage 

 are attacked. 



Distribution 



Throughout the coast citrus belt of 

 Southern California. Also occurs in vari- 

 ous places in the San .loaqnin and Sacra- 

 mento valleys. 



