I've read some on guys using annual clovers that they frost seed where they intend to put brassicas in the fall. The idea being the clover will provide early spring greens for deer even if browsed a good bit and still be a great source of nitrogen for your brassicas to feed on when you switch it over late summer and produce big tops in the fall. Anyone ever try this? Any experience with annual clovers at all? What species or seed did you use?