Subterranean clover living mulch: an alternative method of weed control

Abstract

An alternative method to using herbicides in some crops may be the use of subterranean clover ( Trifolium subterraneum L.) as a living mulch for weed control. Subterranean clover is a self-seeding winter annual legume with a geocarpic type of growth for which it is also known as ‘subclover’. From 1986 to 1990 subterranean clover was used in our research with success in several agronomic and vegetable crops. Our initial work was with field corn ( Zea mays indentata L.). Included in this experiment were treatments of subterranean clover living mulch, rye ( Seacale cereale L.) dead mulch, and no-mulch. Included also were several tillage treatments superimposed on the mulch treatments. These were conventional, minimum, and no-tillage. We later included soy beans [ Glycine max (L.) Merr], sweet corn ( Zea mays saccharata L.) and several vegetables such as summer squash ( Cucurbita pepo L.), spring cabbage ( Brassica oleracea capitata L.), snap beans ( Phaseolus vulgaris L.), and tomatoes ( Lycopersicon esculentum Mill) in our research. We found that subterranean clover used as a living mulch in a no-tillage system provided excellent weed control in all experiments without the use of herbicides. All living mulch-tillage treatments reduced greatly weed biomass. Treatments without subterranean clover living mulch, including the conventional tillage-herbicide treated checks, had higher weed biomass. Yields of corn, sweet corn, cabbage, snap beans and tomato were not adversely affected by the subterranean clover living mulch.