' Mapping the Way to a Higher
Yield'
Ian W. Seaton , B.Sc.
Going through Northern Ireland one constantly comes across fields in which the crop is obviously subdivided into different varieties, each conspicuously labelled. These are
. variety tests, the results of which, carefully collected and compared over a period of years, provide the subject of this talk. It has been found that while results vary enormously from one district to another, there is a very marked tendency towards consistency of result within the same district. This means that the varieties are exhibiting distinct environmental preferences. When the results are set out in map form, these preferences show up quite clearly, and recommendations based on such maps have been exceedingly successful.