Studies on the Weeds of Vegetable Crops IV. Further Observations on the Effects of Different Primary Cultivations

Abstract

In a previous paper (Roberts 1963), the results were described from a 6 year study of the effects of four different primary cultivations on the numbers of weed seeds in the soil at Wellesbourne. During the same period, three other long-term field experiments were in progress at Experimental Horticulture Stations of the Ministry of Agriculture, Fisheries and Food. These three experiments were sponsored and supervised by the National Institute of Agricultural Engineering (N.I.A.E.) and were conducted at Efford E.H.S., Lymington, Hants., Luddington E.H.S., Stratford-on-Avon, Warwicks. and Stockbridge House E.H.S., Cawood, Selby, Yorks. Their object was to determine the effects of different methcods of primary cultivation, with suitable finishing operations, on the yields of vegetable crops and on soil properties. The main comparison in the experiments was of three depths of working; ploughing and rotary cultivation were also compared and the treatments included different methods of traction. During the course of the experiments, observations on the relative degree of weed infestation on the various plots were made by officers of the Experimental Horticulture Stations concerned. In addition, through the courtesy of N.I.A.E., soil samples were taken by the author from selected plots at the end of the first and second cycles of the 3 year rotation in order to determine the cumulative effects of the different treatments on the populations of viable weed seeds present in the soil. The results obtained are described and discussed in the present paper.