Page:Popular Science Monthly Volume 63.djvu/337

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ROPS have been cultivated for thousands of years, and from the very first the agriculturist has endeavored to get from the soil a maximum return for a minimum of labor expended. Yet scientific progress in soil fertilization and crop improvement has been exceedingly slow until very recent years. Now scientific methods are beginning to be applied not only to crop and soil improvement, but also to the allied branches horticulture, arboriculture, the dairying industries, etc. That infant science, bacteriology, in particular, gives promise of inestimable value.

Some microorganisms work in the interests of the agriculturist, while others work decidedly antagonistically to all desirable interests. Much efficient work has been done in the eradication of disease-producing organisms, and the farmer is given detailed and specific instructions how to combat organisms which are hurtful to crops, as the rusts, smuts, rotting bacteria, etc. Attempts have been made to utilize even essentially harmful organisms in working useful results, as in the extermination of chintz bugs, potato beetles, plant lice; the extermination of rats, mice and other undesirable higher animals, by means of germs which are capable of transmitting fatal diseases to the animals referred to. The department of entomology at Washington has done some very effective work of this nature in exterminating insect pests of trees and plants.

The farmer's great future problem will be to determine what beneficial organisms may be pressed into his service and what noxious organisms may be suppressed, and how such measures may be carried out most expeditiously and with the best results. There is perhaps no problem of greater interest or none which gives promise of greater beneficial results than the one pertaining to the bacteria found in the root tubercles or nodules of leguminous plants (bean family). Without entering into the history of the discovery of these organisms or the part they play in the economy of the host plant, or even dwelling upon the many points still in dispute or under discussion, I shall describe briefly some of the recent attempts at making practical agricultural use of these organisms in Europe and in this country, and outline briefly a plan of future research, pointing out the additional practical possibilities which may be anticipated with reasonable certainty, based upon results already obtained.