Is Sulfur Cinquefoil a Candidate for Control with Sheep and Goats?

Project Overview

Project Type: Research and Education
Funds awarded in 2007: $54,250.00
Projected End Date: 12/31/2011
Region: Western
State: Montana
Principal Investigator:
Dr. Jeff Mosley
Montana State University
Rachel Frost
Montana State University

Annual Reports


  • Animals: goats, sheep


  • Animal Production: grazing - multispecies, range improvement
  • Education and Training: demonstration, display, extension, farmer to farmer
  • Pest Management: eradication, field monitoring/scouting, physical control

    Proposal abstract:

    Sulfur cinquefoil is an aggressive invader in the Rocky Mountain West that is found in all but 3 of the lower 48 states and listed as a noxious weed in 5 states. The long-lived perennial weed is a prolific seed producer that is adapted to nearly every soil type and vegetation complex. Sulfur cinquefoil is also capable of colonizing relatively undisturbed plant communities, making it a potential invader on millions of acres. The plant forms dense monocultures that displace native vegetation, threaten biological diversity and reduce forage for wildlife and livestock. Sulfur cinquefoil is closely related to strawberries and other economically important Rosacea species. This combined with the multitude of native cinquefoil species present on rangelands make it a poor candidate for biological control. Herbicides are effective, but require annual re-application until the seedbank is depleted. Sheep and goats are well established as viable control agents for leafy spurge and spotted knapweed, and anecdotal evidence suggests that both herbivores will include sulfur cinquefoil in their diets. The purpose of this research is to determine what combination of timing and intensity of defoliation results in the greatest decrease in yield, vigor, seed production, and seed viability of sulfur cinquefoil. Sulfur cinquefoil contains condensed tannins that are believed to limit intake of the plant by herbivores, however, cattle and wild ungulates have been observed grazing the seedheads in late summer. This study will examine fluctuations in tannin levels throughout the growing season, and whether scarification of seeds in the digestive tract of grazing animals (sheep and goats) influences seed viability and germination. Results will be used to evaluate grazing as a potential control measure for sulfur cinquefoil and to enhance current grazing management techniques to reduce the spread of the weed. The findings of this study will be disseminated to ranchers, livestock producers and land managers to facilitate the control and prevention of sulfur cinquefoil on rangelands.

    Project objectives from proposal:


    There are four separate objectives to this project. Objectives 1-3 are independent research questions that will each produce results that can stand alone. The purpose of objective 4 is to synthesize and distribute the information gained from each of the previous objectives.
    1) Determine the effects of different timings, frequencies and intensities of sulfur cinquefoil defoliation on a) plant yield, b) plant vigor, and c) seed production and viability.
    2) Examine sulfur cinquefoil seeds passing through the digestive tract of sheep and goats for a) time required to complete passage, and b) viability of seeds post scarification.
    3) Evaluate the tannin content of sulfur cinquefoil a) at different phenological stages (pre-flower, flower, and post-flower) and b) in response to clipping.
    4) Synthesize and disseminate the findings of the above projects to county extension agents, educators and grazing managers to facilitate the development of grazing plans that reduce the spread of sulphur cinquefoil.
    Previous research and observations indicate that sheep and goats will consume sulfur cinquefoil, therefore, these objectives are exclusively designed to address: 1) the biological response of the plant to defoliation, 2) the propensity for the grazing livestock to spread viable seed and 3) the chemical composition of the plant at different seasons. With this knowledge in hand, the next logical step would be to conduct actual grazing trials specifically designed to decrease the vigor and reproductive ability of the plant based on the results produced by this project.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.