526 FIELD CROPS 



damp situations, such as are found where the growth 

 of weeds is rank. Weeds may harbor insects by supplying 

 them with food when crop plants are not available, or by 

 furnishing them a safe refuge over winter under rubbish 

 along fence rows or in fields. 



691. Weeds Lower the Value of Crop Products. The 

 presence of weeds or weed seeds in crop products often 

 lowers their value. Buyers of grain quite often make a mate- 

 rial dockage in weight or price for the presence of any notice- 

 able quantity of weed seeds, and this dockage is usually 

 more than is justified by the actual weight of the weed seeds. 

 If the grower removes the seeds before marketing, they 

 increase the cost of production by the labor which is required 

 to separate them from the grain. Weeds in hay materially 

 affect the value of that product for the market or for feeding. 

 Weeds in grain crops make the bundles more bulky and thus 

 more twine is required to harvest the crop. They increase 

 the weight of the crop which must be handled, both of grain 

 and hay. They increase the expense of gathering the crop 

 by delaying harvesting operations, as in cotton, potato, 

 and corn fields. Rank, succulent growth of weeds delays 

 the curing of hay and grain crops, and may thus reduce 

 their quality. 



692. Weeds Injure Pastures. In addition to crowding 

 out useful pasture plants and using plant food and moisture, 

 weeds decrease the value of pastures in other ways. They 

 may be distasteful to animals, either because of their odor 

 or taste or because they are armed with spines or thorns, 

 causing stock to avoid their vicinity and thus allowing a 

 portion of the useful pasture grasses to go to waste. They 

 may injure animals which eat them by causing irritation, as 

 in the case of the beards of wild barley or squirrel-tail grans, 



