Weed seeds are recognized as an important factor in the dietary of our useful birds. Other things being equal, those seeds having the highest nutritive value might be expected to figure more prominently in this regard than seeds less nutritious. In animal feeding, the protein content of the feed is taken as the measure of its nutritive value, and the cost of the feed is determined largely by the protein content as ascertained in the chemical laboratory. Hence the protein content of weed seeds is of some economical importance as related both to the maintenance of our native birds and to the control of the weeds themselves
