Medusahead Invasion as Influenced by Herbicides and Grazing on Low Sagebrush Sites

Abstract

Responses of vegetation following herbicide applications and grazing strengthened previously developed synecological concepts of the low sagebrush community in relation to medusahead invasion. Removal of the shrub cover with 2,4-D did not necessarily lead to an increase in medusahead because the perennial grasses quickly made use of the released environmental potential. Spraying 2,4-D for brush control combined with application of atrazine for herbaceous weed control further increased perennial grasses when not grazed, but with grazing, medusahead greatly increased at the expense of perennial grasses by 3 years after treatment.