SB 
818 
c576 0. 93, REVISED. Issued June 23, 1909. 
si lited States Department of Agriculture, 
BUREAU OF ENTOMOLOGY. 
L. O. HOWARD, Entomologist and Chief of Bureau. 
THE SPRING GRAIN-APHIS OR SO-CALLED “GREEN BUG.” 
(Toxoptera graminum Rond.) 
By Fr M. WEBSTER, 
In Charge of Cereal and Forage-Plant Insect Investigations. 
The early history in America of the spring grain-aphis (figs. 14), 
which has come to be generally known as the “ green bug,” was pub- 
lished in Circular No. 85 of this Bureau, and need not be reproduced 
Fic. 1.—Spring grain-aphis (Toxoptera graminum): Male. Greatly enlarged. (Original.) 
here. Suffice it to say that it is an imported species, long known to be 
destructive to growing grain in Europe, but not known in this country 
prior to 1882, and not as a destructive insect until 1890. The litera- 
ture relating to this, the third and perhaps most destructive outbreak 
of the pest, is so misleading that this publication seems necessary in 
order to prevent misapprehension among farmers, and to afford them 
all possible helpful information in advance of future similar out- 
breaks. 
DISTRIBUTION IN THE UNITED STATES. 
The insect is usually common, and is found from New Mexico, 
Colorado, and Montana to the Atlantic coast, approximately cover- 
ing the area south of latitude 41°, excepting New York, New Jersey, 
and New England, and east of longitude 105°. Within this territory 
its area of destructive abundance, as well as the severity of its at- 
tack during any year, will be regulated by two factors: First, the 
848438—Cir. 93—09—_1 
vY 
ZOO8TA 
