COTTONWOOD IN THE MISSISSIPPI VALLEY. 15 
from this source are especially pronounced in the Red River Valley 
region of Texas and Oklahoma. Although the apparent injury is 
confined to the branches, the vitality of the whole tree is weakened 
through loss of nourishment withdrawn by the parasite. | 
INSECTS. 
Many species of insects attack cottonwood, but with few exceptions 
cause no serious damage to the trees. The exceptions are found in 
one or two species, the larve of which bore into the living bark and 
sapwood, sometimes doing serious damage. If any serious injury 
by insects is found, the matter should be reported to the Bureau of 
Entomology, Department of Agriculture, Washington, D.C. Speci- 
mens of the insects or of their work should accompany such a report. 
ANIMALS. 
The thin bark of young cottonwoods is relished by field mice and 
rabbits, and at times large numbers of trees are completely girdled 
by their gnawing. Girdling by mice is most likely to occur under 
snow or in deep grass. Rodents may destroy most of the young 
trees or cuttings in a cottonwood plantation, which makes planting 
on grassy sites a hazardous undertaking. Seedlings, however, usu- 
ally sprout from the root collar below the injury. In the case of 
natural reproduction, where the trees come up so densely that the 
loss of 75 per cent or more during the first two or three years is 
of little consequence, the damage from this source is but slight. 
Cattle are very fond of the green shoots and fohage of cottonwood 
and should be kept out of young growth, either natural or planted, 
for the first three or four years, after which they will do but little 
harm. 
FIRE. 
Cottonwood is very susceptible to fire injury while young, but bv 
the time it is 15 to 20 years old has produced a fairly fire-resistant 
bark. Fires are, moreover, not likely to start or become serious on 
bottoms subject to overflow. Young cottonwood stands should be 
carefully protected against fire. 
REPRODUCTION. 
FROM SEED. 
Cottonwood reproduces readily both by seed and by sprouts. 
Female trees bear seed in abundance practically every year. They 
begin to seed very early in life, probably when not over 10 years of 
