This section is from the book "The Gardener's Monthly And Horticulturist V23", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
By A. E. Forbes, reprinted from the Bulletin of the Laboratory of Natural History of Illinois.
Many who read the discussions in newspapers must often wonder why people will write an opinion which takes an hour, rather than spend five minutes in looking up the facts in the case. "Are birds any use to the fruit grower?" is one of these questions. The man who has seen the robin eat a pestiferous grub and no more, is sure the robin ought to be preserved; on the other hand, he who knows the robin will eat cherries, knows no more, but is sure the robin is a profound rascal, for whom gunpowder and shot are much too good. Mr. Forbes deserves the thanks of all the lazy bones by the careful investigations here published. People can see here just what the birds do - the good they do and the bad they do - and form a just balance as to their value. In the case of the robin, Mr. Forbes found that in February ninety-five per cent, of the food of the robin was insect food, of which ten per cent. were of insects supposed to be beneficial. Of the larvae of the bibio, which, by the way Mr. Forbes shows to be an injurious insect, were consumed to the amount of 1,500 per month on the average to each bird. In March, a large per cent, of cut-worms formed the food. In April, beetles in large numbers are eaten, a few sumach berries forming the only vegetable food.
In May, seventeen per cent, of its food was of the terribly destructive May beetle, the larvae of which, as the white "grub," florists are .too well acquainted with. A single robin had eaten a single potato beetle. It is well known that birds take to different insects gradually till they get preferences which become habits. It is a pity this bold robin came to an acquaintance with Mr. Forbes' gun, though in the cause of science, as it may have spoiled a race of potato beetle eaters, but it is to be hoped other robins will pursue the same line of investigations. With June, the robin changes his carnivorous habits. While ninety-five per cent, of his food has been of insects before, it is now reduced to forty-two, the balance he takes in tithes from the cherry and raspberry crop. Still he keeps up the war on bad insects, four per cent, of wire worms, among other potions insects being part of his daily food. In July he came up to seventy-nine per cent, of fruit food, and in August forty-four per cent, of his whole food were cherries. In September fifty two per cent, were grapes, mostly wild kinds of the woods, as indeed we suppose were many of the fruits already noted. We have given only a few small items.
Mr. Forbes goes into every thing with a strict detail, that is worthy of a judge of the supreme court. All we have done is to illustrate his manner of going to work. As to the robin, Mr. Forbes concludes the balance is largely in favor of the robin. He says, "I do not believe that the horticulturist can sell his small fruits anywhere in the ordinary markets of the world at so high a price as to the robin, provided that he uses proper diligence that the little hucksters do not overreach him in the bargain." And these are our sentiments. Mr. Forbes goes over the facts in the same way with other birds; but our space will not permit us to refer more particularly to them. We can only say that the paper is not only a valuable contribution to ornithological science, but one that gardeners should be especially thankful for. As the paper is evidently a voluntary contribution to science, and must have taken an immense amount of time to work out in detail, Mr. Forbes is the more entitled to proper gratitude.