30 
Colorado ExpERi]\rENT Station 
response to deficient water supply. The disease organism is carried 
by the seed and it is therefore important to disinfect the seed, par¬ 
ticularly as is known to be unhealthy. 
Control: 
1. Use formalin solution made at the rate of T pound of for¬ 
malin 40 per cent, strength to 40 gallons of water. 
2. Use the sprinkle method described under stinking smut of 
wheat. 
3. The solution should be thoroughly mixed with the seed, 
using about % gallon of solution to 1 bushel of seed. 
4. Allow the seed to stand 5 or 6 hours covered by a canvas 
or wet sacks and then dry by stirring it around. 
5. Fanning before treatment will remove many light weight 
affected seeds. 
6. Rotate crops on infected soil. It is well to remove or burn 
diseased flax straw or stubble. 
7. Do not use fresh or undecayed manure made from infected 
flax straw. Well-decayed manure will contain no spores capable of 
germination. 
Rye. 
Smut.^ This disease is known as stalk smut, stem smut and 
stripe smut. All above ground parts are attacked. The first ap¬ 
pearance of the smut is marked by elongated narrow stripes grayish 
in color. Later the affected tissue appears brownish or black, due 
to the exposure of the black smut spores from beneath the epidermal 
layer. The disease is first noticed usually at heading time. At 
this time the leaves may show rifts or splits lengthwise, and the 
stems are often misshapened and stunted. The heads are almost 
always destroyed and often do not develop. 
The smut spores are spread in threshing or are blown by wind 
to healthy grain. Infection may come either from infected seed 
or from diseased soil. 
Control: 
1. Two things are essential in controlling this disease—crop 
rotation and seed treatment. Stakeman and Levine recommend the 
following method (Bui. 160, Minn. Agr. Exp. Sta.) : 
2. Use formalin 1 pint to 40 gallons of water for seed treat- 
]nent. 
3. Dip the sack of grain into the solution in such a way as to 
wet all the grain, lift it out, drain for a moment, dip again and 
repeat until it is certain all the grain is wet. 
4. Then either keep the grain in the sacks or pile it and cover 
with wet sacks for 4 to 12 hours. 
