Soil Sci. Soc. Am. J. doi:10.2136/sssaj2014.02.0086 Received 27 Feb. 2014. *Corresponding author (andyscott@fs.fed.us). © Soil Science Society of America, 5585 Guilford Rd., Madison WI 53711 USA 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 retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher.