2 BUKLETIX 1275, U. S. DEPARTMENT OF AGRICULTURE 
cent of smut in the Racehorse variety when inoculated kernels 
were sown, as compared with more than 9 per cent in White Australian 
oats grown under similar conditions. 
Jensen (8) , in Denmark, recorded the percentage of smut infection 
in 22 varieties of oats during 1885, 1886, and 1887. In 1885 the 
highest percentage of infection recorded was 28, and several varieties 
were entirely free. The next year the highest percentage of smut 
was 45, and practically all the varieties were infected to a greater 
or less extent. In 1887 the highest percentage of smut was 75, and 
all the cultivated varieties were infected. No special efforts were 
made to inoculate the seed, and the results indicated clearly that in 
successive years there was greater contamination of the seed of the 
different varieties. As no artificial inoculation of the seed was 
made, the experiments are not convincing as to the comparative 
resistance of the varieties. It may be noted, however, that the 
variety Blainsly in general showed the highest percentage of infection 
and further that Avena strigosa Schreb., grown during these same 
years, remained entirely free from infection. 
Kellerman and Swingle (10) mention differences in the prevalence 
of smut in a few varieties of oats. They quote Bartholomew to the 
effect that the earlier and colored varieties, such as . Red Texas 
and Black Winter, suffer more than the white varieties. Hickman 
(5, 6), in Ohio, has recorded the prevalence of smut in a number of 
varieties of oats, most of which showed from 1 to 10 per cent of 
infection. Many varieties, however, showed higher percentages of 
smut, and none proved entirely free. Hickman also noted the 
increase of smut in the varieties in successive years, due to the 
increased contamination of the seed. Selby (16) also has recorded 
the occurrence of smut in oats. All of the 27 varieties recorded by 
him generally showed high percentages of infection. Jones (9) 
noted the occurrence of smut in oat varieties in Vermont and found 
considerable variation in its prevalence in different varieties, none 
showing an}' striking evidences of resistance. Shamel (17) records 
the percentage of smut in 34 varieties grown at the Illinois Agri- 
cultural Experiment Station in 1900. The infection varied from 1 
to 22 per cent. 
Zavitz (23, 24, &5) h^ s noted the marked freedom of Early Ripe 
(Burt) oats from smut. In 1906 he sowed treated seed of five varie- 
ties of oats, all of which remained free from smut. These varieties 
were then grown from 1907 to 1914, inclusive, without tether seed 
treatment. No efforts were made to inoculate the seed, and any 
smutted plants that appeared in the plats as a result of chance con- 
tamination were removed before harvest. During these years as a 
result of chance contamination there was a very marked increase in 
the percentage of smut in Black Tartarian and small percentages in 
Joanette, Siberian, and American Banner. On the other hand, in 
Early Ripe only one smutted head was found in 1913 and two in 1914. 
Various agricultural experiment stations in bulletins or reports 
make more or less casual reference to the prevalence of smut in differ- 
ent varieties of oats. In most cases these records have more signifi- 
cance in indicating the varying degrees of contamination of seed 
than in indicating the possession of resistance on the part of certain 
varieties. 
