A frenulum (or frenum) is a small fold of tissue that prevents an organ in the body from moving too far.
Cover crops usually are grown to prevent soil loss from wind and water erosion. Use fast-growing cover crops, such as winter wheat or annual rye, on fall-spaded gardens. A second, and probably more important reason home gardeners should use cover crops is to improve soil structure and increase organic matter.
The cover crops to plant in the fall are clover, hairy vetch, elbon (cereal) rye, Austrian winter peas, or annual rye. Till these in next spring or anytime before they flower. The exception is elbon rye, which should be tilled in before it reaches a foot tall, or it will be too tough to till.