SB 
818 
1 ipsgete 
> Marae 
C578 
ENT 1O. 8, REVISED EDITION. Issued September 22, 1908. 
aited States Department of Agriculture, 
BUREAU OF ENTOMOLOGY, 
L. O. HOWARD, Entomologist and Chief of Bureau. 
THE IMPORTED ELM LEAF-BEETLE. 
(Galerucella luteola Mill.) 
By C. L. Maruatr, 
Entomologist and Assistant Chief of Bureau. 
GENERAL APPEARANCE AND METHOD OF WORK. 
The chief insect enemy of the elm is the imported elm leaf-beetle, 
the larve and adults of which frequently so disfigure the trees as to 
render them useless for shade and hideous rgther than ornamental. 
The beetle—a small, yellowish-brown insect—appears first and fills 
the leaves with small irregular holes, while the following broods of 
slug-like yellow and black larve skeletonize the leaves in irregular 
spots between the veins, working on both surfaces, but chiefly on 
the lower side, causing the leaves to assume a dry, brown appear- 
ance, to curl, and ultimately to fall. The second crop of leaves 
sent out by the trees in the southern range of the insect meets a 
similar fate. 
DISTRIBUTION. 
This leaf-beetle is a well-known defoliator of elm trees in Europe. 
It is especially abundant in France, southern Germany, and Austria, 
and to a lesser extent in Italy, Corsica, and Sardinia. It was brought 
to the United States about 1837 at Baltimore, Md., and gradually 
spread north and south until at present it reaches as far south as 
Richmond, Va., and as far north as southern New Hampshire on 
the Atlantic seaboard and Ithaca in central New York. For many 
years it confined itself to the Atlantic seaboard, but has now passed 
the Appalachian range and will probably spread through the West, 
conforming in general to the limits of the Upper Austral life zone. 
NATURAL HISTORY AND HABITS. 
CHARACTERISTICS OF DIFFERENT STAGES. 
The insect occurs on the trees in three different stages, and the 
fourth stage is passed on or under the surface of the ground at the 
base of the tree; i. e., the egg, larva, and beetle on the tree, the 
pupa in the ground. 
53931—Cir. 8—08 rd 
¥ 
