Open main menu

Page:Popular Science Monthly Volume 81.djvu/478

This page has been proofread, but needs to be validated.

1/10 of an acre, after the grass thereon had been poisoned with the arsenate of soda spray (strength given above) at the rate of sixty gallons per acre. The animal cropped freely upon this without any ill effect. This poisoning of the grass was repeated twice thereafter, and after allowing her to remain several days in the inclosure after the third spraying, she was removed, to all appearances in even better condition than at the beginning of the experiment.

It is only from an actual test like this that one is justified in making

PSM V81 D478 Mites on a grasshopper.png

Fig. 12. Mites on a Grasshopper.

a statement and even in this case we qualify it by reminding the farmer that carelessness with the mixture might cause a fatal accident. Nevertheless it is evident that, properly used as directed against grasshoppers, no such severe tests as above would arise.

Many will remember a legal case in a western state where a smelting company was sued by a stock owner on the ground that the latter's pasturage was poisoned by arsenic coming from the smelters and the consequent death of the stock. The interesting point of this suit was the fact that the loss did not occur until after several months' feeding on the grass claimed to be poisoned.

An obstacle met with by the farmers in a practical application of this method is the difficulty they experience in obtaining arsenate of soda in sufficient quantity, and at reasonable cost, from the country druggist at the time when it is most needed. The most effective time to spray, and also the most economical, is shortly after the "hoppers" hatch, and long before they obtain wings, and the average farmer is not far-sighted enough to lay in a supply of the poison before hand. It is