Seed Production Characteristics of Three Fine Fescue Species in Residue Management Systems

Published in Agron. J. 103:1495–1502 (2011) Posted online 8 Aug 2011 doi:10.2134/agronj2011.0096 Copyright © 2011 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 retrieval system, without permission in writing from the publisher. T closely related species of Festuca exhibiting fi ne leaf texture are commercially important turfgrasses and are known collectively as the fi ne fescues (Huff and Palazzo, 1998). Th ese species are Chewings fescue (CF), strong creeping red fescue (strong CRF), and slender creeping red fescue (slender CRF). While fi ne fescue species are morphologically similar in many characteristics, strong CRF and slender CRF produce rhizomes, but CF does not. Residue burning has been justifi ed on the basis of pest control and stimulation of seed yield (Hardison, 1980; Chilcote and Young, 1991). Public concern over air quality and the potential for adverse health impacts on the region’s residents has necessitated the identifi cation of alternative residue management practices. Th e benefi cial eff ect of burning on seed yield in the fi ne fescue species group (F. rubra) has long been established, but previously published studies have not always identifi ed which of the fi ne fescue species was being tested. Because taxonomic distinctions within the F. rubra group have been refi ned over time (Huff and Palazzo, 1998), the placement of fi ne fescue cultivars within the described species in previous residue management studies is largely unknown. Musser (1947) showed that fall burning of creeping red fescue increased seed yields because of reduced disease and insect problems. Work by Pumphrey (1965) demonstrated that nonthermal removal of postharvest residues produced seed yield in red fescue that was equivalent to burning. However, Young et al. (1998) reported that the success of nonthermal management in fi ne fescues was species specifi c; seed yield was equivalent with either burning or nonthermal management in CF, but in strong CRF burning was the best practice to maintain economic seed yields. Th e seed yield of cool-season perennial grasses decline as the stand ages, particularly in rhizome-forming species (Canode and Law, 1975). Zapiola et al. (2006) found that fi eld burning maximized seed yield in the latter part of stand life in a single cultivar of strong CRF. Applications of the plant growth regulator, trinexapac-ethyl, improved seed yield in nonburned older stands, but yield remained below the levels attained by burning. Burning reduced rhizome production in strong CRF, resulting in increased fertile tiller production, but fertile tiller production in slender CRF was not aff ected (Meints et al., 2001). Recent Oregon legislation (2009) has, in eff ect, ended the practice of fi eld burning in the state for most species except for the fi ne fescues. A better understanding of species-specifi c responses to residue management in the fi ne fescues will permit producers to choose the appropriate alternative practices should further restrictions become law. ABSTRACT