Statistics, Department of
Date of this Version
2015
Citation
Published in Agron. J. 108:141–150 (2016)
Abstract
Crested wheatgrass [Agropyron cristatum (L.) Gaertn., A. desertorum
(Fisch. ex Link) Schult., and related taxa] often exists
in near monoculture stands in the northern Great Plains.
Introducing locally adapted yellow-flowered alfalfa [Medicago
sativa L. subsp. falcata (L.) Arcang.] would complement crested
wheatgrass. Our objective was to evaluate effects of seeding
date, clethodim {(E) -2-[1-[[(3-chloro-2-propenyl)oxy]imino]
propyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one}
sod suppression, and seeding rate on initial establishment and
stand persistence of Falcata, a predominantly yellow-flowered
alfalfa, no-till interseeded into crested wheatgrass. Research was
initiated in August 2008 at Newcastle, WY; Hettinger, ND;
Fruitdale, SD; and Buffalo, SD. Effects of treatment factors on
plant frequency during initial establishment were influenced by
site environments. Late summer and spring were suitable seeding
dates. Clethodim sod suppression increased seedling frequency
in most cases. Seedling frequency increased as seeding
rate increased from 0.56 to 7.84 kg pure live seed (PLS) ha–1.
Specific seeding dates, clethodim sod suppression, and high
seeding rates did not greatly improve initial establishment when
site environments were poor. Residual effects of seeding date
and sod suppression post establishment were not significant
at most locations, but seeding rate effects were evident. Initial
establishment and persistence of Falcata alfalfa was successful at
Newcastle, indicating that interseeding in late summer or spring
using low seeding rates (≤3.36 kg PLS ha–1) without clethodim
can be effective. Assessing grass canopy cover, soil texture, and
management (e.g., haying) is necessary to determine the suitability
of crested wheatgrass sites for interseeding.
Comments
Copyright © 2016 by the American Society of Agronomy