HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Mitchell, C. C. Articles by Balkcom, K. S. PubMed Articles by Mitchell, C. C. Articles by Balkcom, K. S. Agricola Articles by Mitchell, C. C. Articles by Balkcom, K. S. Related Collections Sustainable Agriculture Crop Rotation Systems Other Crop Management Soil Organic Matter Cotton Maize History Production Agriculture Maize Management

CROP ROTATIONS

A Historical Summary of Alabama's Old Rotation (circa 1896): The World's Oldest, Continuous Cotton Experiment

^a Dep. Agronomy & Soils, Auburn Univ., Auburn, AL 36849
^b USDA Soil Dynamics Lab., S. Donohue Dr., Auburn, AL 36830

^* Corresponding author (mitchc1{at}auburn.edu).

After more than 110 yr, the Old Rotation experiment on the campus of Auburn University in Alabama continues to document the long-term effects of crop rotation and winter legume cover crops on sustainable cotton (Gossypium hirsutum L.) production in the southeastern United States. Long-term yields indicate that winter legumes are as effective as fertilizer N in producing maximum cotton yields and increasing soil organic carbon (SOC). Higher SOC resulted in higher crop yields. However, rotating cotton with corn (Zea mays L.) in a 2-yr rotation or with corn, winter wheat (Triticum aestivum L.), and soybean [Glycine max. (L.) Merr.] in a 3-yr rotation produced little long-term cotton yield advantage beyond that associated with SOC. Cotton yields without winter legumes nor fertilizer N are only slightly higher than they were 110 yr ago. Nonirrigated corn grain yields in rotation with cotton are typically low for central Alabama and appear limited by N. Yields of all crops on the Old Rotation increased with increasing rates of P and K through the 1950s. Since adoption of in-row subsoiling, high-residue, conservation tillage, and genetically modified cultivars in 1997, all crops have produced their highest, nonirrigated, recorded yields since the experiment began: 1910 kg cotton lint ha^–1 in 2006, 14.8 Mg corn grain ha^–1 in 1999, 6.34 Mg wheat ha^–1 in 2001, and 4.50 Mg soybean ha^–1 in 2004.

Abbreviations: SOC, soil organic carbon

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.

Received for publication December 10, 2007.