"A hunter MAY NOT:

hunt migratory birds with the aid of bait, or on or over any baited area;
hunt over any baited area until 10 days after all baiting materials have been removed;
hunt waterfowl or cranes over manipulated planted millet, unless the millet was planted not less than one year prior to hunting;
hunt waterfowl or cranes over crops that have been manipulated, unless the manipulation is a normal agricultural post-harvesting manipulation in accordance with official recommendations of State Extension Specialists of the Cooperative Extension Service of the U.S. Department of Agriculture. "

http://www.tpwd.state.tx.us/huntwild/hunt/season/waterfowl/methods/