4 The Colorado Experiment Station 
able to make the study of this malady a theme for special research. 
Accordingly, May i, 1908, the writer began an intensive investiga¬ 
tion of the trouble and during the past year has been occupied with 
laboratory, greenhouse and field experiments bearing upon the 
cause and possible remedies for the disease. The results of this 
work are given in the pages which follow. 
DISTRIBUTION. 
Within the state of Colorado, the disease occurs generally 
throughout the Gypsum Valley in Eagle county, to a somewhat 
less extent in Garfield county, and at Rocky Ford in the Arkansas 
Valley. Prof. W. Paddock has noted it in the Plateau Valley, Mesa 
county, and between Hotchkiss and Paonia in Delta county. 
So far as our present knowledge goes, it has not been seen in 
the San Luis Valley, or in the Boulder, Longmont, Loveland, Fort 
Collins and Greeley districts. 
In our neighboring states, what appears to be a similar bacterial 
disease has been observed by Professor Northrop in Utah, by 
Professor Wooten in New Mexico, by Professor Wilcox in Ne¬ 
braska, and by Professor Roberts in Kansas. Its occurrence is re¬ 
ported as negative by Professor Nelson for Wyoming, by Professor 
Kennedy for Nevada, by Professor Lewis for Oklahoma, and by 
Professor Ball for Texas. 
DESCRIPTION OE THE DISEASE. 
When a field suffering with this bacterial trouble is viewed as 
a whole, about the only comment which could be made is that the 
growth is short and the alfalfa is a little off color. The rich, dark 
green color in the leaves is absent and the juicy, succulent appear¬ 
ance of the stem, so characteristic of a thrifty stand, is wanting. 
The plants tend to grow more spindling; the leaves often appear 
dwarfed, narrow, light green and have a tendency all along the 
stem and in the growing tip to remain partly closed just as they do 
in cold or dry weather. 
The disease is primarily a stem infection and it is here that 
we find the most valuable characters for diagnosis. In the earliest 
stages, the stem has a watery, semi-transparent, yellowish to olive 
green appearance along one side. This extends down the stem 
from below the point of attachment of a leaf for one to three inter¬ 
nodes. Again, on another side of the stem, the infection may cover 
two or three different internodes or parts of the same ones. Most 
commonly the first three to five internodes are the worst infected. 
Such stems are usually healthy and normal below the ground. Soon 
after they take on this dark, olive green, watery appearance, there 
oozes out from the diseased tissue a thick, clear, viscid liquid which 
spreads over the stem and collects here and there in little bead-like 
