TREATMENTS OF SEED WHEAT FOR LOOSE SMUT 25 
treatments slightly increased the yield. The, treatment at 47° C. 
for 2 hours and 30 minutes was one of the most satisfactory. Plants 
from the seed thus treated contained no loose smut, only a trace of 
bunt, and yielded slightly more than the plants from untreated seed. 
In regard to the application of steam treatments of seed wheat in 
large commercial driers, it may be noted that some engineering 
problems would be encountered — the soaking of 500 bushels of wheat, 
for example, and its transfer to the drier. In the movement of wheat 
in mills gravity flow plays an important role. Wheat which has been 
presoaked for four hours, however, will not flow. 
DISCUSSION 
In experiments dealing with hot-water treatments reported here 
and in experiments with the modified hot-water treatment previously 
reported by the writer (Id), indications of stimulation to germination 
or yield resulting from treatment have never been obtained. On the 
contrary, treated machine-threshed seed invariably germinated lower 
than untreated seed, the seedlings emerged more slowly, the yield was 
reduced except when the rate of seeding of the treated grain was in- 
creased, and the plants from untreated seed contained a relatively 
high percentage of loose smut. 
In a consideration of the value of treatment, however, attention 
must also be given to the fact that benefits other than control of loose 
smut may accrue in the plants grown directly from treated seed. For 
example, Gregory (o) notes that in the State of Indiana "smut-free 
areas are being established in which it is hoped that wheat can be 
maintained free from loose smut for several years" and that "it has 
been demonstrated in Knox and Shelby Counties that a widespread 
use of treated seed will greatly reduce the dangers of the spread of the 
smut. In Knox County it was found last summer that wheat which 
had been treated last year had no smut in it; that which was one year 
from treatment had no smut; two years from treatment there was 
one-quarter per cent; and three years from treatment 2 per cent, 
while in the untreated fields there was an average of 8 per cent." 
It seems that the value of treatment should be greatly increased in 
this system by reducing the need and use of treatment to a minimum 
and by giving full play to the beneficial effects accruing from treat- 
ment. Apparently no data are available, however, showing the net 
gain or loss which eventually results when the effects of treatment are 
considered on subsequent crops sown in smutty or in so-called smut- 
free areas. 
SUMMARY AND CONCLUSIONS 
The modified hot-water treatment of seed wheat (described on 
p. 1) for the control of loose smut is open to three principal 
objections: (1) It is difficult to apply, (2) it soaks the seed, and (3) 
in the presence of broken seed coats it is very injurious to germina- 
tion. Experience gained at home and abroad seems to show that, 
in communities where loose smut in wheat is a factor of considerable 
economic importance, properly equipped cooperative or community 
seed-treatment plants afford the best means to facilitate the appli- 
cation of treatment and to popularize control. Studies therefore 
were made (1) of single bath hot-water treatments to devise, if pos- 
sible, a method less injurious to germination, and (2) of steam 
