998 THE COMPLETE GRAZIER. BOOK xi. 



plied to farmers on a commercial scale for the inoculation of the seeds 

 of beans, peas, vetches, clover, &c., before sowing, so as to ensure the 

 presence of the proper organisms for the " infection " of the roots of the 

 young plant as soon as it appears. The practical utility of this 

 " inoculative " treatment on any given soil can only be ascertained by 

 actual experience. 



All other farm crops appear to be dependent for their nitrogen either 

 on the soil, or on the manure added to the soil ; and all crops are 

 wholly dependent upon the soil and on the manure by which it is 

 enriched for the mineral or ash constituents that form an important 

 integral part of every plant. Of these the most important are phos- 

 phoric acid, potash, and lime. These, with nitrogen, comprise, practically 

 speaking, the constituents of plant food about which the farmer has to 

 concern himself. 



But it is always to be remembered that it is a portion only of what 

 crops require from the soil that is thus directly added in the form of 

 manure. A great deal of plant food is drawn from the main stock or 

 capital of fertility which has in earlier times accumulated in the soil 

 itself, and the presence of which in abundance distinguishes the rich 

 soil from the poor one. 



Fortunately for the permanence of our farming system, nature will 

 not allow us to draw very excessively upon the main stock of plant 

 food in the soil, and any attempt to over-force the soil by injudicious 

 farming is met by a temporary exhaustion, which, however, punishes the 

 occupier rather than the landlord. In fact the occupier of a farm 

 cannot, except in the closing years of his tenancy, very well overstrain 

 the resources of the soil without subsequently suffering for it himself. 

 It is, however, legitimate and customary for him to get as much out of 

 the soil as he can in return for his rent, and most of the customs of 

 good farming which have been evolved by practice, assisted in some 

 directions by science, may be regarded as so many modes of making the 

 most of the inherent food of the soil by developing its availability and 

 by supplementing it in the directions that are desirable. The choice 

 and rotations of crops, tillage operations, cleaning, draining, liming, are 

 all so many means of developing the soil food, for the right of using 

 which the tenant pays annually; and manuring in one form or the 

 other is the means adopted for adding to and making the most of the 

 soil food which is by nature and by art annually rendered available. 



GREEN MANURING. In some districts it is found to be good practice 

 to grow certain green crops in the intervals between ordinary rotation 

 crops and to plough them in, their function being to retain for the use 

 of subsequent crops certain solid food that might else be washed away 

 in drainage, and to add to the soil certain constituents derived directly 

 or indirectly from the air. Vetches, mustard, and rape are examples of 

 crops suitable for this purpose. They are usually grown after wheat, 

 and occupy the place of the bare winter fallow that ordinarily occurs 

 between the harvesting of the wheat crop and the sowing of roots. If 

 green food falls short in the early spring, or if hay is scarce, they will 

 come in usefully for sheep, and in failing this they can be economically 



