Bulletin 151, Truck and Garden Insects


just below the surface of the ground. The adult beetle feeds on
the leaves of beans and cowpeas. The larva feeds on the roots
of the same plants, particularly the nodules of the nitrogen-
fixing bacteria. For this reason the insects are a serious pest
when occurring in large numbers.
 If these beetles become numerous in a field of beans, the
plants should be sprayed with a solution of bordeaux mixture
containing a pound of lead arsenate to 50 gallons of the bor-
deaux. (See introduction for directions for making bordeaux
mixture.)
 OTHER BEAN PESTS
 Other insect-pests attacking beans are: Root-knot nema-
tode (see under general garden pests, page 128) ; cutworms (see
under cabbage, page 137) ; corn ear-worm (see under corn, page
151), sometimes mines the pods; cabbage looper (see under
cabbage, page 140), sometimes eats the leaves; cowpea pod-
weevil (see under cowpeas, page 160) ; grasshoppers (see under
general garden pests, page 122) are troublesome in the fall;
pumpkin bug (see under cowpeas, page 161) and other plant-
bugs (see under potatoes, page 177) are among the most trouble-
some enemies of the bean grower; garden aphid (see under
cabbage, page 144); wireworms (see under corn, page 153);
flea-beetles (see under beets, page 136) ; and striped cucumber-
beetle (see under cucumbers, page 166).

 LIMA BEANS
 GALL-WORM (Monoptiloba sp.)
 In addition to the pests of other beans, lima beans are
attacked by a caterpillar that bores into the stems. The plant
thus attacked forms a large swelling or gall about the larva.
In this gall the larva lives, feeding on the tissue until its growth
is complete. The adult insect emerges as a small moth, and
lays eggs on the stems of the plant. These galls are very com-
mon on lima beans in Florida. There seems to be no practical
means of preventing this injury. If the beans are well fertil-
ized and cultivated they will bear well in spite of this insect.

 BEETS
 BLISTER-BEETLES
 These long, slender beetles feed on a variety of truck
plants, including beets, tomatoes and potatoes. In the Northern
States these insects are known as old-fashioned potato bugs "