SOME INSECTS INJURIOUS TO VEGETABLE 
CROPS. 
THE POTATO STALK WEEVIL. 
( Trichobaris trinotata Say.) 
One of the important insect enemies of the potato, and a common 
species almost everywhere east of the Rocky Mountains and south of 
New England, is a little gray weevil, whose larva works normally in 
the stems of wild Solanacez, such as horse nettle, ground cherry, and 
jimson weed, in most fields where these plants are allowed to grow. 
The habits of this insect and its manner of attacking potato have 
been known for half a century, the first instance of injury having been 
noticed in 1849 near Philadelphia, Pa. Since that time the injuries 
inflicted by it to potato have attracted considerable attention, periodi- 
cally and locally, especially during the last decade, and there is reason 
to believe that it is often present and doing damage, though unde- 
tected, in potato fields, where the insect itself has never been seen. 
Its habit of living within the stem in its larval condition, and the 
small size of the beetles, together with their habit of dropping from 
the plants when disturbed, is accountable for injury by the species so 
often escaping notice. Hence it happens that, although a pest of 
long standing, the insect is unknown to many potato growers. 
During 1900 this species was reported to have done injury near 
Philadelphia, Pa., and South Holland, Ill., and to have been quite 
prevalent in Maryland on potato; but injury was without doubt much 
more extensive than reported. In 1901 the potato crop of Sheridan 
County, Nebr., was nearly ruined by this insect, and it made its initial 
appearance in Canada, doing much damage on Pelee Island. 
In earlier years more or less damage to the potato crop was com- 
mitted in other portions of Nebraska, Illinois, Pennsylvania, and 
Maryland, as well as in Kansas. 
DESCRIPTION. 
The beetle.—The adult potato stalk weevil is a Small ash-gray weevil, 
or snout-beetle, of the family Curculionide. Its real color is black 
throughout, but its surface is covered with minute gray scales, which 
give ita nearly uniform gray appearance. The head, however, appears 
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