Brett Muirhead (MSc student)

Brett holds a BSc Agric degree in Applied Plant and Soil Sciences. He comes from a farming background, working with crops and livestock which has led him to pursue a career path in sustainable agriculture. His passion and ambitions paved the pathway to a masters degree in pasture agronomy focussing on the benefits and forage quality of cover crops interseeded into maize.

The modern-day farmer is challenged by a higher demand for food production and quality food sources. To solve this problem, the farmer needs to optimise his total yield production and decrease arable land degradation. The utilization of cover crops is a proven conservation practice in agriculture. Cover crops contribute to the reduction of land degradation and soil erosion. Characteristics include increased soil water infiltration, storage capacity, microbial biomass, soil nutrients and microbial biodiversity. This resulting in an improved environment for cash crops to succeed. The common implementation of cover crops is in a crop rotation as the monospecific crop but for better utilization of resources, cover crops can be intercropped or interseeded into a cash crop. The system of integrating livestock grazing and interseeding a mixed cover crop into maize (Zea mays), is a new and valuable practice for the farming community. This project will determine to what extent does interspecies specific competition between the mixed cover crop and the maize crop influence the effects on soil properties and associated maize crop yields. Further observations on the post maize harvest cover crop forage value and quality will be recorded. The mixed cover crop interseeded into the maize consisted of one grass, two legumes and two brassicas. The dry matter production for the post maize harvest mixed cover crop was recorded at an average of 2 ton/ha. The best performers in the mixture, in terms of biomass accumulation and competitive abilities, were Stooling Rye (Secale cereale) and Turnip (Brassica rapa). The performance of the different species within the mixture were highly dependent on the specific environmental conditions and date of planting. The interseeded mixed cover crop proved to be compatible with the maize crop and provided additional grazing resources for livestock over a longer period of time.