Get reliable rangeland science

Tall-forb communities occur an 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 flower 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 1993 was unsuccessful. Forb and grass production is expected to return to levels similar to those on untreated areas after 5 years. This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries. The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020