SEED AND SEED SELECTION 35 



were lamb's-quarter or pigweeds; the same pound also 

 had 3126 seeds of dodder. Another pound carried 6420 

 seeds of crabgrass, and one had 3325 seeds of foxtail. 



The station authorities recommend that no alfalfa seed 

 be sown until carefully screened through a screen jfine 

 enough to remove dodder seeds. Wire sieves or screens 

 with twenty meshes to the inch are found to serve the 

 purpose. 



ADULTERANTS BESCRIBED AND IliliXJSTRATED. 



As a further and more thorough discussion of the fre- 

 quent adulterants, Prof. H. F. Roberts, botanist of the 

 Kansas experiment station, has kindly prepared for this 

 volume the quoted statements which follow here, also 

 their illustrations, from photographs made under his 

 direct supervision : 



"The immense and steadily increasing value of alfalfa 

 as a forage crop in the United States, and the high price 

 of the seed, make the securing of sound, pure seed a 

 matter of supreme importance to farmers, and render it 

 equally important for them to be able to recosniize, by 

 sight/the presence in alfalfa seed of the addterants 

 and seeds of certain weeds most commonly known to 

 occur. There is conclusive evidence that an amount of 

 adulteration and substitution is actually practiced with 

 alfalfa seed. It is usually charg-ed that this is done 

 abroad, especiaUy. as is aBeged. ta Germany. 



"The writer has been informed that, to a limited 

 extent, the practice exists in America* The chief adul- 

 terant used is the seed of the Yellow trefoil, or, as it is 

 sometimes called. Hop clover or Black medick. There 



