Hedgcock and Hunt : Dothichiza populea in the U. S. 307 
alone or in association with Dothichiza populea Sacc. & Briard. 
The relationship of the two fungi in the United States will be 
made the subject of further investigation. It has, however, been 
collected on Populus tremuloides as follows : At Middlebury, Vt., 
by E. A. Burt, April, 1896,® and at Orono, Maine, by P. L. Ricker, 
May 14, 1898.® 
Suggestions for the Control of the Disease 
This disease apparently has its main centers of infection in our 
nurseries, and it is here that the first work of control should 
begin. All poplar trees that are blighted in the twigs or limbs or 
that show cankers should be dug out and burned. It will be 
better for the nurseryman to err on the side of caution than to 
allow this disease to gain a foothold in his nursery. A small 
infected twig on an otherwise healthy tree may infect all the trees 
in a bundle of transplants, and once infected the trees are ruined, 
as the fungus kills them back and spoils their beauty. 
Poplars planted as ornamentals that become badly diseased 
should be dug up, removed, and burned. This treatment may 
seem to be severe, but in view of the fact that the disease appears 
to be a dangerous one it is the only safe course to pursue if it is 
to be exterminated. This disease has been under observation for 
a short time only, and no experiments for its control have been 
made. 
Delacroix, among other suggestions, recommends the following 
treatment for the disease, but does not report its effect : The de- 
struction of all diseased trees or diseased material; the disinfec- 
tion of tools used in this work ; the disinfection of the clothing 
and hands of workmen thus engaged ; and the dipping of cuttings 
before planting in an acidulated Bordeaux mixture containing at 
least 10 per cent, of copper sulphate. 
The writers would be glad to receive specimens of this and of 
other poplar diseases from as many localities as possible. 
Bureau of Plant Industry, 
U. S. Department of Agriculture. 
5 Ellis, J. B., and Everhart, B. M. North American Fungi. No. 3536. 
1898. 
6 Ricker, P. L. Flora of Maine. No. 388. 1898. 
