Published in Agron. J. 104:1065–1073 (2012) Posted online 29 May 2012 doi:10.2134/agronj2012.0109 Copyright © 2012 by the American Society of Agronomy, 5585 Guilford Road, Madison, WI 53711. All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retr...