WHAT BIRDS DO FOR US 13 



"Certain garden weeds produce an incredible number of 

 seeds," says Dr. Sylvester Judd, of the Biological Survey. 

 *^A single plant of one of these species may mature as 

 many as a hundred thousand seeds in a season, and if un- 

 checked would produce in the spring of the third year ten 

 billion plants." With these figures in mind, it is easy to 

 account for the exceedingly rapid spread of certain weeds 

 from the Old World — daisies and wild carrot, for example 

 — of comparatively recent introduction here. The great 

 majority of weeds being annuals, the parent plant dyiag 

 after frost or one season's growth and the species Uving 

 only in embryo during the remainder of the year, it fol- 

 lows that seed-eating birds are of enormous practical 

 value. Even the despised Enghsh sparrows do great good 

 as weed destroyers — almost enough to tip the scales of 

 justice in their favor. In autumn, what noisy flocks of the 

 little gamins settle on our lawns and clean oflF seeds of 

 crab-grass, dandelion, plantain, and other upstarts in the 

 turf ! The song sparrow, the chipping sparrow, the white- 

 throated sparrow, and the goldfinch are glad enough to 

 follow after their English cousin and get out the dandelion 

 seeds exposed after he cuts off several long, protecting 

 scales of the involucre. Because of his special preference, 

 however, the httle black and yellow goldfinch, an un- 

 equaled destroyer of the composite weeds, is often called 

 the thistle-bird. The few tender sparrows which must 

 winter in the South are replaced in autumn by hardier rel- 

 atives, whose feeding grounds at the Far North are buried 

 under snow; by juncos, snowflakes, longspurs, redpoUs, 

 grosbeaks, and siskins, aU of which are busy gleaners 

 among the plow furrows in fallow land, and the brown weed 

 stalks that flank the roadsides or rear themselves above 



