WHEAT — WEEDS, INSECTS, DISEASES 339 



with a seed-plat on which the grain to be used in seeding 

 the general crop is groWn.^ 



417. Covered smut, stinking smut or bunt. — This 

 smut produces its spores exclusively within the kernel, the 

 chaff being unaffected. When the diseased kernels, are 

 examined they are found to be completely filled with a 

 black, dust-like mass, which has a "pecuhar fetid odor 

 like that of decaying fish." In the thra;Shing and other- 

 wise handling the grains from the diseased crop, the 

 smutted kernels are broken and the spores find lodgment 

 on the sound grains. They are thus carried over to the 

 next crop. As the spores of this disease do not mature 

 until the grains are mature, they are carried over only on 

 the surface of the grains and can be killed by any method 

 that thoroughly disinfects the outside seed-coat\ The 

 spores of the loose smut mature when the grain is in bloom 

 and hence get into the flowers, from which they penetrate 

 the young kernels. The important seed treatments for 

 covered smut are the following : 



Hot-water treatment. — Soak the seed for 10 to 15 

 minutes in water kept at a temperature of from 132° to 

 183° F. The seed should be immediately dried following 

 the treatment. 



Formalin treatment. — Thoroughly moisten the seed 

 with a solution made by mixing one pound of formalin to 

 every 45 gallons of water. The' grain may ,be either 

 sprinkled or soaked, the essential point being the thorough 

 wetting of every kernel. If sowing is done immediately 

 the seed should be dried sufficiently to run through th6 

 drills. Seed that is to be kept any length of time after 

 being treated should be spread out on a clean floot and 

 thoroughly dried. 



' Farmers Bui., 507, p. 27. 



