treatment difficulties in handling and sowing the grain, and (3) it 
severely injures or kills the germination of seeds with broken coats 
(15), and the percentage of broken seed coats in machine-threshed 
wheat frequently runs high (7, 15). 
The experience gained abroad and in this country seems to show 
that in communities where loose smut in wheat is a factor of con- 
siderable economic importance a solution of the problem of applica- 
tion lies in the establishment of cooperative or community plants 
for seed treatment. According to Mercer (11) and others, the modi- 
fied hot-water treatment has been used so extensively in coopera- 
tive dairies in Denmark that the disease is now said to be practically 
exterminated. In this country, in the State of Indiana particularly, 
as shown by Pipal (13) and Gregory (5), the modified treatment has 
received a big impetus since 1918, the year in which the first com- 
munity plant in that State began operations. 
The investigations reported here were therefore conducted to study 
and devise, if possible, a practical method or methods (1) yielding 
effective control but less injurious to germination, or (2) whereby 
the seed could be dried with facility after treatment, or both. 
The methods studied were: (1) Treatments in which the seed in a 
porous container was simply immersed in a single bath of water 
maintained at a constant temperature. This is called the "single- 
bath" " method in the following pages. According to Humphrey 
and Potter (6) it is less injurious to germination than the modified 
method. (2) Steam treatments. The seed was first presoaked, then 
steamed in a commercial grain drier. 
Attention is called to the fact that the single-bath and steam treat- 
ments were studied only from the viewpoint of application at coopera- 
tive or community seed-treatment plants. Their application involves 
the maintenance of constant temperatures for relatively long periods 
and other factors which make them hardly practicable of application 
by the individual farmer. 
SINGLE-BATH HOT-WATER TREATMENTS 
PREVIOUS INVESTIGATIONS 
Experiments on the use of single-bath hot-water treatments for 
controlling loose smut of wheat or barley, or both, have been reported 
by a number of investigators. A comprehensive review is given by 
Appel and Riehm (1) of the various means employed by different 
investigators to control these diseases, including the single-bath 
treatment and other modifications of the hot-water method devised 
by Jensen (8). More recently Humphrey and Potter (6) have 
studied further the limitations of temperature and duration of treat- 
ment within which control may be satisfactorily effected by this 
method. 
With barley satisfactory control frequently has been reported from 
treatment of the seed for two hours at 45° C. With wheat, however, 
satisfactory control evidently was less often obtained. The tempera- 
tures and durations of treatment used vary widely. Humphrey and 
Potter (6) recommend a three-hour immersion at 113° F. (45° C.) 
> Referred to as the" Dauerbad" by Appel and Riehm (/) and the "long hot-water" or "Pasteurization" 
method by Humphrey and Pottei (6). 
