244 SECTIONAL ADDRESSES 



by the aid of the fertiHsing effect of the sheep fold. This is claimed to be 

 necessary, not only to build up suitable reserves of plant food, but to 

 secure satisfactory physical structure in these loose, shallow soils. It is 

 worthy of note that the idea finds some confirmation in researches now 

 proceeding at Rothamsted. None the less, I am inclined to think that, even 

 if com growing again becomes profitable, other methods of maintaining 

 soil fertility will be adopted. 



The system of arable sheep farming which, in its fully developed form, 

 is peculiar to some of the southern and eastern districts of England can 

 not only claim to be a form of intensive farming with relatively high 

 production and employment of a large amount of labour, but it is also the 

 system under which the mutton qualities of many of the British breeds 

 were developed. To it may largely be attributed the clear supremacy 

 which our breeds enjoy in all countries where sheep are kept primarily 

 for the production of meat. The work of Hammond and others has 

 clearly shown that genetic variability in size, rate of growth, early maturity, 

 and general carcase quality is only fully expressed under optimum 

 conditions of nutrition. Under less satisfactory conditions, the animal 

 of exceptionally high potential characters may be indistinguishable from 

 the individual which is merely moderately good. This variability must 

 be secured if improvement by selection is to be effected, and the reduction 

 in arable sheep is therefore not without its disquieting aspect to the live- 

 stock improver. It will be noticed that the fourteen counties already 

 referred to include the homes of all our Down breeds except the Shrop- 

 shire. It is not improbable that the Shropshire also has suffered to the 

 same extent, and that the maintenance of the sheep population in the 

 native county of the breed is due to a great and overriding influx of grass 

 sheep from the Welsh border. 



The Longwools were in the main developed originally on good grass 

 land liberally supplemented with produce of arable crops. The Down 

 breeds originated in districts where there is little good grassland, and owe 

 their improvement largely to breeders whose selective methods were 

 aided by the ample food supplies provided by a succession of arable crops. 



For modern conditions, the Longwools with their large, excessively fat 

 carcases, and the Downs, handicapped by the cost of labour and other 

 considerations already discussed, are (as the table shows) falling behind as 

 commercial sheep. It will, however, be necessary for ram-breeding 

 flocks to be continued — even if only to provide rams for crossing pur- 

 poses — and for such flocks some system of arable management would 

 appear to be practically essential, if the standard of our sheep is to be 

 maintained. 



The Production of Fat Lambs is no new feature of British sheep farming, 

 but during the last thirty or forty years it has attained an importance far 

 exceeding its position in any previous period, and now probably the 

 majority of lambs not to be kept for breeding purposes are sold for 

 slaughter before they are six months old. Changing demands are the 

 main reasons for this development. Formerly, early fat lamb was 

 regarded as a luxury article only to be consumed by wealthy or extravagant 

 people. Now, regardless of cost, the public demands small joints of 



