45 2 
Journal of Agricultural Research 
Vol. xxvn, No. 7 
Putterill (40) found the disease in the Marico district of the Transvaal, 
South Africa, in 1920. He states that it has probably been present a 
number of years and that, although the total loss is not great, 50 per 
cent of the plants may be affected in some fields. Flag smut also is 
known to occur in China (49, 50). 
Flag smut was found in the United States for the first time in May, 
1919, according to Humphrey and Johnson (19). It was found then in 
a number of fields in the vicinity of Granite City, Madison County, Ill. 
As a result of a survey made in 1920, the disease was found over an area 
of approximately 47 square miles (51). In 1921 the quarantine zone was 
extended to include 61 square miles. It is pointed out, however (45), 
that this is not necessarily due to spread of the disease but that a more 
intensive survey was possible in 1921. 
The relative importance of the disease varies considerably in the vari¬ 
ous countries in which it is now known to exist. It would appear that in 
Australia the conditions necessary for the perpetuation of the pathogene 
have been especially favorable, for in that country flag smut is of the 
greatest importance. 
In 1891, Cobb (9) stated that the disease was a serious plague. Brittle- 
bank (4) in 1920 states that the prevalence of flag smut has increased to 
an alarming extent in recent years throughout the wheat-growing areas of 
Victoria, Australia. He states that since stem rust may ruin a crop in a 
few days under favorable weather conditions, many have considered it as 
the most destructive disease of cereals in Australia, but flag smut annually 
takes a toll of from 5 to 70 per cent of the crop, so that the total annual loss 
from rust sinks into insignificance when compared to that caused by 
flag smut. 
Bartlett (2), in a report on a district wheat crop competition in New 
South Wales, Australia, in 1922, states that flag smut considerably 
reduced the yield of many crops, and mentions losses as high as 30 per 
cent of the crop in certain fields. 
The amount of damage caused by the disease in any particular locality 
in a given year often may be closely correlated with environmental 
conditions and cultural practices. Hence, although it is not possible to 
give an accurate estimate of the total losses due to flag smut in Australia, 
there is sufficient evidence to show that the disease is widespread in the 
States concerned, and fairly conservative estimates place the average 
annual loss for Australia at 3 per cent. 
The situation in India is one of great interest. Butler (7) states that 
the disease is confined to the Punjab. It has been many years since it 
was first recorded from that country, and, although apparently there 
have been opportunities for the disease to spread to other localities, it 
has not been found in any other wheat-growing areas. 
Haskell, according to Stakman (45, p. 162-164), reports that the 
disease may cause considerable damage in western Illinois, where as many 
as 25 per cent of the plants have been diseased in certain fields. How¬ 
ever, although the known region of infestation is apparently increasing, 
the disease evidently is being held in check or even reduced on individual 
farms. 
THE DISEASE 
SYMPTOMS 
The first symptoms are more or less elongated grayish or dull white 
stripes on the young leaf. These stripes are slightly raised above the 
