Response of montane tall-forb communities to 2,4-D and mixtures of 2,4-D and picloram

Murray, R.B. and Mayland, H.F. and Shewmaker, G.E. (1991) Response of montane tall-forb communities to 2,4-D and mixtures of 2,4-D and picloram. Journal of Range Management. 44(4):311-318.

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Abstract

Tall-forb communities occur on deep soils of the upper montane
and subalpine zones of the Rocky Mountains and extend from
southwestern Montana to southern Utah. In the Centennial
Mountains of Montana, forbs comprise >80% of the annual
yields, including 30-35% sticky geranium (Geranium viscosissimum)
and 20-25% Potentilla spp. Tall-forb communities are rich
in species diversity and very productive, but many of the forbs are
not palatable to grazing ungulates. Suppression of the less palatable
species, like sticky geranium, would increase the forage value
for grazing. In 1983 and 1984 adjacent plots were sprayed during
weeks 1, 2, 3, and 4 in July, with 2,4-D[(2,4 Dichlorophenoxy)acetic
acid, isooctyl ester] applied at 1.1 or 2.2 kg 2,4-D/ha or
2.2 kg 2,4-D/ha plus 0.6 kg/ha of the potassium salt of picloram
(4-amino-3,5,6-trichloropicolinic acid). Forage yields were measured
in August of 1984, 85, and 86. Total forage yields ranged
from 2,700 to 3,000 kg/ha on the untreated areas. Forb yields were
significantly reduced, especially by the 2,4-D + picloram treatment.
Herbicide treatments applied during flower-stalk development to
first fower of sticky geranium were most effective. Grass and sedge
production partially compensated for reductions in forb yields.
Interseeding of introduced species into herbicide treated plots in
1983 was unsuccessful. Forb and grass production is expected to
return to levels similar to those on untreated areas after 5 years.

Item Type:	Article
NWISRL Publication Number:	0746
Subjects:	Mass Import - unclassified
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:53
Last Modified:	07 Dec 2016 00:00
Item ID:	556
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/556