BUCKWHEAT 591 



entire failure in many localities of New York on account 

 of such blasting. Rather high temperatures are appar- 

 ently not so destructive if the nights are cool. The time 

 between flowering and formation of grain is a critical one 

 in the life of the plant, dry weather or very hot weather 

 at this time reducing the yield of grain very materially. 

 Pullman (1909) found that .under the conditions of the 

 experiment, temperatures of 1 and 2 C. did no 

 harm to buckwheat seedlings, but at 2.5 C. the 

 tenderest leaves began to suffer; at 4 nearly all 

 the plants were damaged, while at 6 they were killed. 

 A type has been developed in Russia which resists 4. 



CULTIVATION 



657. Seed cleaning and grading. Large seeds of 

 buckwheat will produce larger plants and more grain than 

 small seeds. Cleaning and grading of the seed should 

 result, then, in more vigorous plants, a more even stand, 

 and better yields. The removal of foreign material, such 

 as sticks and straw, from the seed will allow of more uni- 

 form seeding. Since there are no important fungous 

 diseases, no special treatment of the seed is necessary 

 for disease prevention. 



Buckwheat grain can be used for seed immediately after 

 harvesting. After the second, or at most the third year, 

 it loses its power of germination, although retaining still 

 its value for food. 



658. Preparation of soil. Buckwheat is most fre- 

 quently sown on seed-beds hastily and carelessly pre- 

 pared, due to its being used so often as a crop on left-over 

 land or where other crops have failed. The land is plowed, 

 then harrowed, and sown immediately afterwards, no 



