GRAIN SMUTS. 



To the ordinary observer nothing could seem more unlike a 

 definitely organized plant than the black, dusty mass filling the kernels 

 of wheat or replacing an entire head of oats. Yet, as a matter of fact, 

 the black dust is composed of thousands of germs of a minute parasitic 

 plant. These germs, or spores, which have the same function as the 

 seeds of higher plants, are blown about by the wind and lodge on the 

 healthy kernels of the grain. When the kernel sprouts the spores 

 adhering to it germinate and send a slender thread into the young 

 plant. The slender threads of the parasite follow the growth of the 

 plant, but their presence can scarcely be detected until the head begins 

 to develop. The flower or grain is then filled by a mass of the threads, 

 which absorb the nourishment intended for the grain and are soon con- 

 verted into a mass of spores, again ready to fly about and infect next 

 year's seed. 



There are two classes of smuts which attack our common cereals, 

 viz., the stinking smuts, which destroy only the kernel, and which have 

 a pronounced disagreeable odor, and the loose smuts, which destroy 

 not only the kernel but also more or less of the chaff, and which are 

 more dusty and loose. The stinking smuts occur on wheat only, while 

 the loose smuts are found on wheat, oats and barley. As the different 

 smuts have to be treated differently, it is of advantage to the agricul- 

 turist to be able to recognize them readily. Wheat, for instance, is 

 attacked by three species — -two stinking smuts and one loose smut. 



STINKING SMUTS OF WHEAT. 



The two species are very similar and can usually be distinguished 

 only by the aid of a microscope. The smutted kernels (usually all in 

 the head are affected) are slightly larger and more irregular in shape 

 than healthy grains, and are easily broken open, disclosing a dark- 

 brown powder, which possesses a disagreeable penetrating odor. 



