. Bulletin. Animaux -- United States ; oiseaux -- United States. Cardinaux COMME DESTROYERS DE MAUVAISES HERBES. 13. Fig. D âSeeds Lithosperminn arvensc grémil (maïs). (À partir de Ilillman, Nevada Experiment Station.) oiseaux granivores, et leur grande valeur pour l'agriculteur consiste dans le service qu'ils rendent dans cette direction. Le combat contre les semences, si coûteux pour lui, est menée par l'ensemble du corps de moineaux et autres oiseaux granivores, année après année sans interruption. Si ce n'était pour eux le nombre de mauvaises herbes w o u 1 d'être bien plus important et la re- sulting dommages cor- respondingly plus grand. Comment grand ce barrage- ag

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. Bulletin. Animals -- United States; Birds -- United States. CARDINALS AS WEED DESTROYERS. 13. Fig. âSeeds of corn gromwell (Lithosperminn arvensc). (From Ilillman, Nevada Experiment Station.) seed-eating birds, and their great value to the farmer consists in the service they render in this direction. The warfare against seeds, so costly to him, is waged by the whole body of sparrows and other seed-eating birds year in and year out without cessation. Were it not for them the number of weeds w o u 1 d be vastly greater and the re- sulting damage cor- respondingly larger. How great this dam- age is will appear from the statement that the loss to the wheat interests of Minnesota from dockage, largely due to the presence of weed seed, is about $2, 500, 000 annually.« Moreover, conditions in Minnesota are not exceptional, and in every State the total annual loss from weed seeds is very great. So far, then, as farmers can protect and increase the number of weed-seed eating birds to that extent will they reap the benefit of increased service from these faithful servants. The redbird eats the seeds of many of the most harmful weeds, making more than a third of its subsistence upon them. Hence it occupies a very impor- tant place among the weed-destroying birds, and should be prized accordingly. Animal Food. Though in quantity much less than the vegetable food, the animal portion of the cardinal's diet is much more diverse and is comprised in no less than six of the natural classes. These are myriapods, centi- pedes, insects, spiders, bivalves, and univalves. Insects are vasth^ more important than the others a n d constitute 26.25 out of 28.99 percent, the total proportion of animal matter consumed. The percentage is appor- tioned among the orders of insects as follows: Wasps 0.92, bugs 3.72, butterflies (and caterpillars) 5.1, grasshoppers G.42, and beetles 10.48. # ^â t. ^^^ ^^ Fig. (5.âSeeds of ragweed (Ambrositi (irfcminiaefolia). imiman, Nevada Experiment Station.)

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