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.
1 The traditional yellow yarrow is quite popular, but other colors look great in the garden and are equally deer resistant.  Coreopsis (Tickseed): Coreopsis spreads easily and comes in a variety of colors. It's also hardy and deer resistant, making it a great choice for gardens plagued by deer problems.