GRASSES OF IOWA. 

 TABLE NO. IV. 



101 



Cereals. — An article on this subject would hardly be com- 

 plete without something in regard to the purity of the seed 

 grain of this country. As a rule they have a very high stand- 

 ard of purity; 99 per cent pure is the government standard, 

 and that established by McCarthy was over 97. 5 per cent. The 

 seeds of a few weeds are usually to be found in wheat seed and 

 to a lesser extent in oats. The most frequent of these are 

 chess or cheat {Bromus secalinus), corn cockle {Lychnis githago), 

 sheep sorrel [Rumex acetosella), pigeon grass, foxtail {Chaetochloa), 

 rib grass {Plantago lanceolata) and garlic {Allium vineale). W. 

 S. Devol,* who examined several samples of wheat seed, states 

 that the seed of chess may be present in wheat at the rate of 

 9,000 per bushel and still amount to only about one-tenth of 

 1 per cent, and that the seed of corn cockle at the rate of 1,888 

 seeds per bushel would make only six-hundredths of 1 per cent 

 of the total. Let us have a pure seed league with the motto, 

 "An ounce of prevention is worth a pound of cure. " 



VITALITY. 



It is a well known fact that the seeds of grasses have a com- 

 paratively low vitality. It is also a fact, though perhaps not 

 so generally known, that the vitality of the average sample of 

 commercial grass seed, as determined in germination tests, is 

 much below what may be taken as an average standard. In 

 fact, the average vitality of commercial grass seed is consid- 

 erably lower in proportion to this reasonable standard for 

 grass seeds than are the average vitalities of most other com- 

 mercial seeds in proportion to the reasonable standards deter- 

 mined for them. 



There are several reasons which, taken together, will largely 

 account for this state of affairs. In the first place, the seeds 



*Pourth Ann. Report Ohio Agri. Exp. Station. 1885: 183-186. 



