Rye grass. If you let annual rye head out and mature in the spring, your "Annual" Rye will automatically become Perennial. Problem I had with pasturing over the winter is the time and money put into the crop just to see the cows stomp it to death, especially during rainy periods. Just decided to put the money in hay and supplements as required. Benefit is in the spring when the cutter comes out, you can stay in your tractor seat while you get a decent spring cutting. Double cropping with Coastal Bermuda gives you the best of both worlds......Rye comes off when the Bermuda starts to grow, or if running a SS summer crop, planting time is right there.