1916] 
DUGGAR—THE TEXAS ROOT ROT FUNGUS 13 
Herbaceous plants: Beta vulgaris, Chenopodium sp., Cas- 
sia Tora, C. marilandica, Medicago sativa, Arachis hypogaea, 
Phaseolus vulgaris, Vigna sinensis, Linum rigidum, Croton 
spp., Euphorbia spp. (three), Sida spinosa, Hibiscus esculen- 
tus, Gossypium herbaceum, Petroselinum hortense, Ipomoea 
Batatas, Solanum rostratum, Ambrosia psilostachya, and 
Xanthium canadense. 
So far as I am aware, no special attempt has been made to 
determine all the species of wild herbaceous plants or forest 
trees affected. The enumeration of hosts given above makes 
it seem plausible, therefore, that few plants or crops may be 
free from the disease except the grains and other members of 
the grass family. At Petty, Texas, in September, 1901, the 
disease was found upon half a dozen species of weeds in a 
pasture, the sod of which could not have been disturbed for 
some years previous. 
The chief characteristic of the disease, as far as I have ob- 
served it on herbaceous plants, is the sudden wilting and dy- 
ing of the affected individuals. Occasionally a slight yellow- 
ing and unhealthy appearance is found to be due to an infec- 
tion which does not encircle the main root, and less frequently 
to the localization of the disease in a few of the larger primary 
root branches. The first ‘‘dying’’ of cotton is associated with 
the beginning of blossoming, or of boll formation, commonly 
from June to July; but Pammel reports one case in which the 
disease was observed May 6. If the fungus is responsible 
for injuries in the early stages of growth, then either such in- 
juries have been overlooked or have been ascribed to other 
causes. 
common with Rhizoctonia Crocorum the organism 
spreads radially, the rate of spread being most variable and, 
of course, governed by the conditions. The most rapid 
spread observed by the writer was in a field of irrigated al- 
falfa. The persistence of the larger ‘‘dead spots’’ season 
after season in much the same part of the field is accountable 
in large measure for the popular belief that these are ‘‘al- 
kali” spots. The progress of the disease from one year to 
another is best followed by observing a perennial crop such 
as alfalfa, in which case new infections are usually relatively 
few, whereas in a field grown two years or more to cotton 
