GRAIN SMUTS. 553 



Even a small per cent of smutted kernels will give a whole bin of wheat 

 this characteristic odor. The stinking smuts are thus easily recognized 

 if present in any considerable quantity in the thrashed grain. This is 

 not true of any other grain smuts, however. 



LOOSE SMUT OF WHEAT. 



This is very different from the stinking smuts. It has no fetid odor; 

 attacks both kernels and chaff; ripens when the healthy wheat is just 

 flowering; and is composed of a loose, dusty mass of spores. These 

 spores are usually entirely blown away by harvest time, leaving only 

 the naked stalk where the head should be. 



Loose smut is known to occur in many parts of the United States, 

 though fortunately it is rare or entirely absent in many localities. It 

 does not usually destroy so large a proportion of the crop as do the 

 stinking smuts; still, it often causes a loss of ten per cent or more of 

 the crop, and has even been reported as destroying over fifty per cent 

 of a crop in Michigan. 



Wheat growers should be on their guard against this enemy, and try 

 to secure seed wheat from fields known by careful examination at 

 flowering time to be free from loose smut. It can, however, be com- 

 batted by treating enough wheat to furnish seed for the following year, 

 and this should be done when any considerable per cent of the crop is 

 affected. 



LOOSE SMUT OF OATS. 



This smut is very similar in general appearance to the loose smut of 

 wheat and like that species it ripens when the grain is in flower, and is 

 blown about by the wind. At harvest time the head is often entirely 

 bare. There is, however, a form of this smut which destroys only the 

 kernel and leaves the outer chaff unaffected. This is very hard to 

 recognize, since the smutted heads look almost exactly like those of 

 healthy plants, and can be detected only by cutting open the husks, 

 when a mass of smut will be found in place of the kernel. Sometimes 

 more than two-thirds of the smut is of this hidden form. This is likely 

 to cause the grower to greatly underestimate the amount of smut. 



By means of two newly discovered treatments of the seed, viz, with 

 potassium sulphide, and with hot water, oat smut can be completely 

 prevented at very little expense. Fortunately, both the common and 

 hidden forms of smut can be eradicated with equal ease. It is certain 



