I have an area for a new pen and i was thinking of planting some type of grass or cover crop that they can pick through and destroy. I know it wont last long term. Any suggestions on type? I was thinking oats or a winter rye. The birds wont occupy new area for at least a month or maybe two. The soil is not in the best shape, sandy, water is easily available. I do live in an area with minor frost. Thank you.