Studies of the effect of wind reduction on soyabeans

Abstract

A preliminary experiment to assess the effect of wind protection on soyabeans var. “Disoy” was made at Lincoln using a “Manx-leg” arrangement of artificial screens (nominal permeability 35ʅ) to provide shelter. In the most protected lee area (protection against NE and NW winds) vegetative production was increased ∼100% and dry seed yield ∼30% compared to unprotected plants, but a storm prematurely ended the growing season before seeds were fully ripened. Until this time, wind run over the plants in the most protected area was reduced by 62%, average windspeed being 3.09km∖hr compared to 8.14km∖hr over exposed plants. Evaporation (measured only in the latter half of the growing season) averaged 3.40 and 4.29 mm per day over the sheltered and exposed areas respectively, a difference of 21.5%. Serial sampling of soil in the 0–15 cm horizon revealed that soil moisture in the exposed plot was significantly reduced in comparison to that in the most protected plot during the first 4 weeks or so of growth, but thereafter the converse was true, presumably as a result of the greater moisture need by the faster growing plants of the sheltered zone.