1906.] 



Bare Fallows. 



3 



ings during the summer. The harrow is used after each plough- 

 ing to collect the weeds, and many farmers roll the land to reduce 

 the clods and promote the germination of the weeds. But on 

 many soils it is desirable to avoid getting too fine a tilth, lest 

 heavy rains cause the land to run together and the surface to 

 set to a hard crust. To this danger the heavy loams and clays 

 with an admixture of fine sand are more liable than the clays 

 proper. 



A bare fallow may exert a beneficial effect on the land in three 

 ways — by cleaning the land of weeds, by improving the texture of 

 the soil, and lastly by increasing its fertility. The continued culti- 

 vations and repeated draggings will rid the land of couch ; at the 

 same time annual weeds are germinated and destroyed by the 

 next ploughing. It may be said, however, that with reasonable 

 farming land should never get so foul as to require a bare 

 fallow to clean it, and we find among the clay-land farmers that 

 their chief justification for a bare fallow lies in the great im- 

 provement in the texture of the soil that results. A clay soil 

 is in the main composed of very fine particles, which, to a certain 

 extent, bind themselves loosely together and act as larger par- 

 ticles. Any knocking about of the soil when wet breaks up 

 these little groups into their constituent fine grains, thus in- 

 creasing both the holding power of the soil when wet and its 

 tendency to dry to a hard clod. Exposure to the weather, on 

 the contrary, freezings and thawings, alternate dryings and wet- 

 tings, unite the particles again and lighten the texture of the 

 soil. With the best of management the texture of heavy clay 

 land tends to deteriorate under cultivation, and the rest it gets 

 by lying under grass for a year or two, or from a summer's fallow, 

 is necessary from time to time to get the soil back into a good 

 working condition. The irhprovement persists for three or four 

 years and forms the main reason for taking a bare fallow 

 nowadays, for good crops, particularly of roots, depend more 

 on the tilth of the seed-bed than on any other single factor in 

 farming. 



Many have been the theories as to whether the land gained or 

 lost fertility through a summer's fallow. Thaer, who was an 

 authority about the beginning of the eighteenth century, wrote : 

 " There is no doubt that the fallow absorbs or attracts the 



B 2 



