78 Smuts [CH. 
smutted field unless measures are taken to kill the 
spores. 
In the case of group A, which attacks the host at 
the seedling stage, the spores are sown with the grain. 
Lines of procedure consist in employing some method 
which will kill the spore and not injure the grain. 
Numerous experiments have been carried out with this 
object in view, and from them the following methods 
have been shown to give satisfactory results. 
In Method 1 blue stone (copper sulphate) is used to 
kill the spores. A clean wooden or concrete floor is 
best for this treatment. A sack (i. 4 bushels) of 
grain is emptied on this floor. The copper sulphate 
solution is made by dissolving 1 Ib. of copper sulphate 
in 1 gallon of soft water. The grain is then thoroughly 
moistened by turning it over and watering it with this 
solution. It should be turned several times and 
allowed to stand for about 10 hours. It is then spread 
in a thin layer until dry, when it is fit for sowing. 
Another way of using copper sulphate is to dissolve 
about 2 Ibs. of it in 10 gallons of water and pour the 
grain into this, leaving it there for about 14 hours. The 
copper sulphate is then run off, and the grain is spread 
to dry. This method kills the smut spores, but it also 
hinders the germination of the grain, especially of oats 
and barley, and should not be used for them. The 
loss is said to be lessened by watering with milk of 
lime, or dusting with lime after treatment. 
Any seed left over after sowing should not be 
used for feeding purposes as the copper sulphate is 
harmful. 
In Method 2 commercial formaldehyde is used to 
kill the spores. It contains nearly 40 per cent. 
