278 USEFUL BIRDS. 



assistance from birds in our gardens than in our woodlands 

 or fields. Nevertheless, the few species that follow the 

 plow and glean among the various vegetables are of the ut- 

 most value to the farmer, who in the ordinary course must 

 depend largely on them to protect his crops from certain 

 insects that are difficult of control. Cutworms, army worms, 

 and cabbage worms are a fewof the garden pests which are 

 eaten by birds, and which birds might control if sufficiently 

 numerous. The squash bug and the Colorado potato beetle 

 are two insects which are seldom eaten, or by but few birds. 



Many of the birds of garden and field may be brought to 

 assist the farmer in his battle against weeds. A weed is a 

 useful plant in nature, and fulfils its purpose by filling bar- 

 ren or unoccupied soil with roots, preventing a waste of that 

 most valuable fertilizing constituent, nitrogen, and adding, 

 by its decay, to the amount of humus and plant food in the 

 soil. In the garden and field, however, these wild plants 

 are out of place, for the farmer wishes to cultivate the 

 corn, the bean, the potato, or other useful plants and various 

 grasses, all of which, if left to themselves, may be dwarfed, 

 stifled, or replaced by a vigorous growth of weeds, which 

 spring up unbidden from the soil. 



Dr. Judd tells us that a single plant of one species of 

 weed may mature as many as a hundred thousand seeds in 

 a season ; and if these were unchecked, they might in the 

 third year produce ten million plants. In competition with 

 this bewildering multiplication, the corn or the bean, the 

 wheat or the rye, with their comparatively few seeds, must 

 soon succumb. 



Constant use of the cultivator and hoe will do much to 

 eradicate weeds from cultivated land, but they are always 

 present in the grass field ; and, as most of the grass is cut 

 after the seeds have ripened, and fed to farm animals, there 

 are always weed seeds present in the manure which is used 

 in garden and field. Thus the farmer annually sows weed 

 seed in his cultivated land. 



Even when the garden is kept clear of weeds, there are 

 still weeds around the edges of fields and gardens, and along 

 roadsides, ditches, and hedgerows, which continually seed 



