398 Seeds and Seedage 



through heredity and environment is more difficult, as it 

 must be made from the product of the plants, often requir- 

 ing special and expert training on the part of the investi- 

 gator. Such determinations have apparently not received 

 the attention they deserve, largely from the prevalent opin- 

 ion that these matters lie beyond the control or check af- 

 forded by the tests of impartial investigators, an opinion 

 no doubt strengthened by the so-called contract often 

 printed on seed-packets to the effect that the seller assumes 

 no responsibility for the contents of the packet. The seed 

 dealer certainly cannot be held responsible for failures that 

 may be fairly associated with conditions of weather, soil, 

 or method of growing ; but the disclaimer cannot shield him 

 if he is negligent or remiss, or if he fails to exercise rea- 

 sonable caution in the care and selection of his stock. Un- 

 doubtedly the quality of seeds is improving, as seed- 

 control laws become more exact, as the good practice of 

 plant-breeding becomes better understood, and with the 

 increasing care on the part of seedsmen. 



Testing for impurities. 



Testing samples to determine the foreign matter (as 

 sand, stones, sticks, chaff, empty seeds), or the presence of 

 seeds of other species is performed by carefully examining 

 small lots under a lens. The operator should have at hand 

 for comparison reliable samples of the seeds of weeds and 

 other plants likely to occur in any sample. 



In the vegetable-garden seeds there need be little fear 

 that many weeds will be introduced. Such seeds are sold 

 in small quantities and they are most carefully cleaned. 

 Even if weeds were to be introduced, the thinning and till- 

 age of a vegetable-garden would eradicate them. The 



