INSECTS INJURIOUS TO MISCELLANEOUS CROPS 249 



LETTUCE 



Of minor truck plants, which will be considered in this chap- 

 ter, lettuce appears, on account of its tender leaves and lack of 

 decided flavor, the most favored by insects. It does not seem 

 to have any insects specially attached to it, but there is one 

 species, the lettuce earth-louse, which may fall in this category. 

 At least a score of species are known to affect it occasionally. 

 Among the most troublesome of these are the common cabbage 

 looper and celery worm, treated in the consideration of insects 

 which affect cabbage and celery respectively. Cutworms are 

 not partial to lettuce, but some species, particularly the va- 

 riegated cutworm, attack it ; a species of thousand-legged worm 

 has been recorded as being very destructive by attacking the 

 outside leaves near the main stalk and four species of aphides 

 or plant-lice are recorded as feeding on lettuce. 



The Lettuce Earth-louse (Rhicobiiis lactucce Fitch). — This 

 common eastern species occurs sometimes in destructive num- 

 bers at the roots of lettuce. It is oval, dull whitish, with dusky 

 legs and antennae, and measures less than one-tenth of an inch. 

 The entire body is coated as though dusted with a whitish 

 powder. It should be treated in the same manner as the root- 

 aphides to which group it belongs. 



OKRA OR GUMBO 



The insect enemies of okra are practically the same as of 

 cotton, which belongs to the same botanical family. Okra, 

 however, is little damaged, and the writer has for several years 

 seen plantings that were not seemingly at all injured by the 

 few insects which were present. One of the principal enemies 

 of okra is the melon aphis, which sometimes occurs upon it in 

 great numbers. The bollworm enters the pods, but evinces no 

 special fondness for them. Several leafhoppers are foimd on 

 okra, and of these is the waved sharpshooter (Oiiconictopia 



