1922.] 



Trials of New Varieties or Cereals. 



339 



portions of different races of grasses. This results from the 

 combined effects of artificial and natural selection and of 

 adaptation, and there is no apparent reason why cereal races 

 should not show a similar range of adaptability. 



The plant breeder is limited in the early stages of the produc- 

 tion of new races by the type of soil of his breeding plots and 

 by the average climatic conditions of his station. The- compara 

 tive yields and qualities of a particular race obtained at a station 

 in the West of England, say on the upper greensand with an 

 average rainfall of 36 in., may be quite different from those 

 obtained, say on the " boulder clays " of East Anglia with a 

 24 in. rainfall. It therefore does not necessarily follow that the 

 plant breeder's original determinations of relative productivity, 

 however correct for his own conditions, will always be applicable 

 to other localities. 



Seasonal effects, even in a limited area, are very diverse. 

 These together with the necessarily variable methods of 

 manuring, crop rotation, and tillage may suit one race of a 

 species better than another. Moreover, in some localities a 

 quick-growing race may be necessary in the average of a series 

 of years, as for instance the quickly maturing " Scotch 

 Common " barley in Aberdeenshire. As a general rule, the 

 more slowly maturing races will be the most productive, but 

 superior yield may have to be sacrificed, if in, say one season 

 out of three, there is a chance that the crop would fail to ripen. 



It follows that all that can usefully be accomplished in any 

 one year in the way of variety testing is to make accurate 

 comparisons of races in respect of respective economic value, 

 taking both quantity and quality into account, at different 

 stations, selected for typical differences both of soil and of 

 average climatic conditions. 



Ts the task of the cereal breeder then a hopeless one? Is an 

 organization for testing new cereal races equally hopeless? 

 It is by no means necessary to accept " counsels of despair," 

 but ip interpreting results of trials it is necessary to keep fully 

 in mind the limitations and qualifications set forth above. These 

 ar ein fact instinctively present to the minds of most growers, 

 and it is because the practical farmer is aware of them that he 

 frequently pays scant respect to variety trials and prefers to 

 rely on his own experiences. 



If it were desired to obtain systematic knowledge of the 

 suitability ( of existing races to localities, no better plan could 

 be adopted than for some representative body, like the Farm rs' 



