216 



COMMON DISEASES OF CROPS 



to finding the best methods of combating these fungous 

 growths. 



To control smut upon corn, it is best to rotate the crops 

 and to destroy the affected stalks before the silvery mem- 

 brane about the spores breaks. Seeds of small grain, like 

 rye, barley, wheat, and oats, should be dipped in a solution 

 containing thirty gallons of water to one pint of formalin. 

 The grain may be placed in a sack for this purpose, and 



soaked for about ten 

 minutes. The seed must 

 then be dried immedi- 



jl sffi/' J% J^ atel 7- The cost of this 



I f |fl 'sW treatment is very small 



in proportion to its 

 benefits. 



160. Rust, one of the 

 chief kinds of fungous 

 growth, gets its name 

 from the fact that it has 

 somewhat the appear- 

 ance of iron rust. The 



most important varieties 

 This affects stalk, tassel, silk, husks, o f rugts are tnose tnat 



and kernels. 



attack clover, beans, 



wheat, and roses. Although the number of species runs 

 up into the hundreds, and although they affect a great 

 variety of plants, both wild and cultivated, their presence 

 often escapes notice. Wheat rust produces yellowish 

 patches on the stem and leaves; and while it does not 

 destroy the plant, it reduces its vitality to such an extent 

 that there results a considerable falling off in the wheat 

 yields. Other rusts act in a like way upon their respect- 

 ive plants. 



No satisfactory method of fighting this trouble has been 



CORN SMUT. 



