4 € 
Among truck and vegetable crops, leguminous plants are greatly 
injured, more especially beans, including Lima beans. Cucumbers 
and tomatoes grown in hothouses, cantaloupes or muskmelons, water- 
melons, and squash are also badly damaged. Eggplant, pepper, 
pepino (Solanum muricatum), corn, cowpeas, raspberry, strawberry, 
beets, and celery are also subject to attack, but are not as a general 
rule very seriously injured. 
Of field crops infested other than those which have been mentioned 
are hops, hemp, peanut, and the groundnut or wild bean (Apios 
cpios). 
Trees grown for shade and for fruit are subject to attack and con- 
siderable injury is effected at times. The list of trees that have come 
under observation as subject to the greatest injury includes the Ken- 
tucky coffee tree (Gymnocladus Miia oe the hop tree (Ptelea 
ty ifoliata) , pecan, ornamental sassafras, arborvite, maple, horse- 
chestnut, and birch. 
INJURY TO TRUCK CROPS. 
Every year this species is noted in considerable numbers on the 
underside of leaves of bean in and. about the District of Columbia, 
frequently causing great blotches and the withering of a large portion 
of the leaf. When the mites occur in such abundance it necessarily 
causes a drain on the vitality of the plant and a decrease in the pro- 
ductiveness of seed-pods if not of the seeds themselves. Still, as a 
rule, such injury is rarely noticed until comparatively late in the sea- 
son, in September and October. 
Similar injury has been reported in Georgia and South Carolina to 
all forms of beans—snap, butter, and Lima—as well as to cowpeas. 
In the same States injury has been reported to a variety of other 
truck crops. Writing in June, one of our correspondents stated that 
his cucumbers fosiceal as if a blight were on them; another wrote: 
“A fine garden three weeks ago now looks as if a fire had struck it.” 
INJURY TO TREES. 
Injury by the red spider to shade and fruit trees 1s insignificant, 
as a rule, compared with that which is accomplished by leaf-feeders 
such as caterpillars. Sometimes, however, very considerable defolia- 
tion is caused by the attack of this species. This was very noticeable 
during the summer of 1906, when the foliage of various shade trees 
in the city of Washington was injured. Attack was first observed 
during the third week in July and was manifested by the leaves hay- 
ing turned yellow on the upper surface. The leaves on the lower 
branches showed the presence of numerous feeding colonies. The 
Kentucky coffee tree suffered most of all of our city trees. On one 
of these trees the leaves continued to drop throughout the remainder 
of July and August, but by September, partly owing to an unpre- 
cedented rainfall of three weeks’ duration, the mites were less in evi- 
[Cir. 104] 
