Provisional land grouping for selection of cultivation requirement for winter barley in Scotland

Abstract

A concept of land grouping is presented which allows the selection of the primary cultivation requirement for winter barley according to soil and site characteristics. The grouping was developed from consideration of the results of field experiments, and from farmers′ and advisors′ experiences. Land is allocated to groups principally according to the probability of compaction occurring in the growing season, which restricts crop performance and which needs to be relieved by cultivation before sowing. Some data from field experiments undertaken at S.I.A.E. are discussed to illustrate the development of the grouping system. The three groups of cultivation requirement are: (1) direct drilling (no cultivation); (2) shallow ploughing or shallow cultivation to 50–150-mm depth; (3) mouldboard ploughing to > 150-mm depth. Land is allocated to these cultivation groups according to the two main factors of topsoil-texture and subsoil permeability. The average topsoil texture and subsoil permeability of the series from soil maps give indicative cultivation grouping. They have been identified for all arable soil series and a selection is given. Allowance for the effect of specific site factors such as date of return to field capacity, slope, soil depth and stone content is made by assessing these locally and adjusting the cultivation group as necessary. The method of allocating soils to the cultivation groups described is intended for use by advisors as an aid to farmers wishing to reduce fuel and labour inputs and preserve soil structure.