4 BULLETIN 1284, U. S. DEPARTMENT OF AGRICULTURE 
The first record of the occurrence of this smut in the United States 
was made in 1888 by Burrill (19), who noted the appearance of the 
smut in Illinois on broomcorn and sorghum. Webber (119) recorded 
it on "millo maize" from Nebraska in 1889, and in 1890 Failyer and 
Willard (38) recorded it on several imported varieties of sorghum 
grown for the first time at the Kansas Agricultural Experiment 
Station. Kellerman and Swingle (58) in 1890 gave a more com- 
plete account of the first occurrence of the smut in Kansas, stating 
that several of the sorghum varieties had been obtained through the 
United States consul at Calcutta, India, while others had been 
imported from Africa. In 1906 Clinton (26) recorded its occurrence 
in 13 States, as well as in Ontario, Canada, and in Jamaica and 
Cuba. 
Covered kernel smut was recognized by Clinton (22) as an impor- 
tant disease of broomcorn in Illinois, and Giissow (43) called atten- 
tion to its destructiveness on the same crop in Canada. It is par- 
ticularly prevalent, however, in the sorghum belt of the southern 
Great Plains area, attacking sorgo, broomcorn, kafir, durra, kaoliang, 
Sudan grass, etc. 
Doubtless most of the damage caused by the sorghum smuts is 
due to the covered kernel smut. Kulkarni (63) estimated that the 
damage to the sorghum crop in the Bombay Presidency is 10 per 
cent, amounting annually to about £1,350,000. Melchers (73) has 
estimated that the annual loss to kafir, broomcorn, and other sor- 
ghums in Kansas is at least $400,000. Probably the annual loss in 
the entire United States amounts to $3,000,000. The amount of 
damage varies greatly in different localities and in different seasons. 
It is not uncommon to find from 30 to 40 per cent of infection in 
some fields. Ordinarily, however, the percentage of infected plants 
is much smaller, and many fields may be entirely free from smut. 
The damage is due to the destruction of the grain. The loss is 
complete in the sorghums used for grain only, and the value of sor- 
ghums used for forage is greatly decreased when the grain is destroyed, 
as smutted plants have only about half the feeding value of normal 
plants. vSmutted broomcorn plants generally are a total loss, because 
the brush usually is of inferior quality, and the plants frequently 
have an excessive development of the thickened central axis and 
branches of unequal length. The smut spores also may be scattered 
over good brush in harvesting, discoloring it and thus lessening its 
value. 
SvJiacelotheca sorghiis a typical kernel smut, the individual ovaries 
of the flowers being involved and converted into false kernels or smut 
balls. (PI. I). Usually all the ovaries are transformed into the smut 
balls, but it is not uncommon to find normal kernels produced on 
infected heads. An infected sorghum plant is quite normal in size 
and general appearance, and the presence of the disease can be recog- 
nized only when the head emerges from the sheath. The glumes 
surrounding the flowers are essentially unchanged, retaining their 
normal size and color, although sometimes they have a purplish tinge. 
The size of the smut balls varies considerably in different varieties. 
In some cases they remain small and concealed by the glumes. 
Usually, however, the ovary is greatly hypertfqphied, giving rise 
to a conical or cylindrical structure 3 to 12 millimeters in length 
