EXERCISE 53 



IMPURITY OF FARM SEEDS 



Statement. The value of a seed depends first upon its vitality. If it will not grow well, then all other 

 considerations are of no value. Next comes the quality of the seed. Pure-bred and pedigreed seeds 

 are always to be preferred, but we have not begun to pedigree clovers and grasses generally. However, 

 something of quality may be judged by the size, brightness, and uniformity of the seeds. The amount of 

 impurities affects their value in two ways. Cracked and broken seeds, trash, and chaff add to the bulk 

 and cause the farmer to pay more for the seed he actually obtains. Much more harmful, however, are 

 the weed seeds acquired with impure seed, because they add to the cost of the seed purchased and 

 cause much damage to the cultivated crops, or else entail expense in keeping the weeds in check. 



Object. To determine the comparative value of seed samples. 



Materials. Commercial seeds of red and alsike clover, alfalfa, timothy, etc. 



Directions. Determine by actual calculation from the samples the relative amounts of dirt in the 

 seed, the amount of weed seed, and the amount of seed of the kind supposed to have been bought. 

 Then count out ioo grains of seed from the weediest sample and ioo grains from the purest sample 

 of the same kind of seed and plant both lots to determine whether more or less of the weedy seed 

 than of the pure seed is growing seed. 



Questions. Can you determine what kinds of weed seeds are present in the above samples ? What 

 are the objections against buying and using seed which contains weed seed ? Which sample contains 

 dirt ? What is the actual cost per bushel of pure seed obtained from the poor seed purchased because 

 of its low price? 



References. Hillman, T. H. " Testing Farm Seeds in the Home and the Rural Schools," Farmers' Bulletin 

 428, United States Department of Agriculture. Davis, K. C. Productive Plant Husbandry, pp. 50-53. J. B. 

 Lippincott Company. 



69. Some noxious weed seeds found in farm seeds 

 a, sand burr ; b, wild oat ; c, chess ; d, darnel ; e, quack grass ; /, dock ; g, black bindweed ; h, Russian thistle ; »', corn cockle ; f, 

 k, bladder campion ; /, night-flowering catchfly ; m, cow cockle ; », penny cress ; o, field peppergrass ; p, large-fruited false flax ; 

 false flax ; r, ball mustard ; s, black mustard ; /, English charlock. Enlarged and natural size 



[1061 



white campion; 

 q, small-fruited 



