To build up and maintain fertility in the soil, feed a large part of the crops and return the manure to the land. If manure is not available, plow under crops grown for the purpose. Plow deep (but do not subsoil). Grow leguminous crops for the nitrogen they add to the soil. Commercial fertilizers and lime may be important means of improving the soil, but the fertilizer requirements of different soils and different crops in different seasons are so little understood that we are not yet in a position to make positive recommendations that are of a general application.

From the foregoing it is evident that silver foxes can be and in fact, are being propagated in confinement. Like most new enterprises, fox raising is a business regarding which opinions vary. The favorable facts are that silver foxes are easily and securely kept in simple wire inclosures; that suitable food for them is cheap and easily obtainable; that they are not subject to serious diseases and that their disposition and quality of their fur can be improved by selective breeding. Opposed to these are the unfavorable facts that they are by nature suspicious, nervous, and not inclined to repose confidence in man; and that, largely for these reasons, they do not breed regularly and successfully, except when cared for by experienced persons more or less gifted in handling them. The number of persons now engaged in the business is relatively small, and the work is still experimental, yet many of the initial difficulties already have been overcome. Numerous minor failures seem explainable in large measure, and are offset by several conspicuous successes. It is therefore probable that under proper management fox raising will be developed into a profitable industry, and it is perhaps not too much to expect that a domestic breed of foxes will be produced. Only time can show how far such expectations will be realized, but present indications must be regarded as very encouraging.