PLANT DISEASES AND INSECT PESTS 



157 



on close examination of a field, are caused by smut. There 

 are several different kinds of smut, all of which are quite 

 common. All the smuts may be controlled by proper 

 treatment. Some of them are easily controlled, while 

 others are more difficult to handle. Every farmer or farm 

 boy may easily know the different smuts and the best means 

 of controlling them. It is very common for smuts to cause 

 a loss of 10 per cent in a grain crop. This means a loss of 

 from $1 to $2 per acre. This loss may be prevented at a 

 cost of only a few cents per acre. 



Loose smut of oats, and covered smut of wheat and 

 barley are very easily controlled by treating the seed grain. 



The smut spores, or seeds 

 of the smut plant, live 

 over winter on the kernels 

 of grain. If the kernels 

 of grain are brought in 

 contact with a solution 

 of formalin, the smut 

 spores are killed. Forty 

 per cent formaldehyde 

 may be purchased at any 

 drug store, — a pint bot- 



Figure 68. — Material and JquipmenHor treat- 1\q j^i\\ cOSt frOm thirty 

 ing certain kinds of grain smuts. ... . , , *^ 



~ to Sixty cents^ — and when 

 mked with 45 gallons of water will make enough solution 

 to treat 60 or 80 bushels of seed grain. There are ma- 

 chines on the market for treating seed grain for smut, 

 or the grain may be spread on the floor and the 

 solution sprinkled over it with a sprinkling can. The grain 

 must be shoveled over so that all kernels come in contact 

 with the solution. It is well to cover the gram after it is 

 treated with sacks or blankets so that the gas from the 

 formaUn will help in killing the smut spores. We give con- 

 siderable space to these smuts, because they attack very 

 important crops, are very common, almost universal, and 

 are so very easily and simply treated. 



Loose smut of wheat and barley causes the whole heads 

 of the plants to fail to produce seed, and instead of the usual 

 head of grain there is nothing left but the bare naked stalk. 



