Impacts of Intensive Rotational Grazing on Stream Ecology and Water Quality

Project Overview

Project Type: Research and Education
Funds awarded in 1995: $43,488.00
Projected End Date: 12/31/1998
Matching Non-Federal Funds: $96,396.00
Region: North Central
State: Wisconsin
Project Coordinator:
Laura Paine
University of Wisconsin-Madison
Dan Undersander
University of Wisconsin-Madison

Annual Reports


  • Animals: bovine
  • Animal Products: dairy


  • Animal Production: grazing - rotational
  • Education and Training: on-farm/ranch research
  • Farm Business Management: agricultural finance
  • Natural Resources/Environment: habitat enhancement, riparian buffers, riverbank protection


    The goals of this study were to determine whether intensive rotational grazing (IRG) can be used to allow farmers to harvest forage from riparian areas without compromising water quality and riparian habitats and to produce guidelines for environmentally sound management of riparian pastures.

    Methods. A total of 21 farms were used as study sites during the two years of the study. All sites were located along spring-fed streams with potential for trout production. Trout streams are a source of recreational and tourism income for local communities, but are often heavily impacted by agricultural land use. Streamside vegetation was managed either as a grassy bufferstrip, a continuously grazed pasture, a rotationally grazed pasture or a woody bufferstrips (limited data collected). We collected data in the following areas: forage production and vegetation community, fish community and aquatic habitat, grassland birds, small mammals, amphibians.

    Results. Rotational pastures produced much more forage than continuous pastures. The average amount of available forage on offer was 1,856 lb/a for ready-to-graze rotational pastures and 781 lb/a for continuous pastures. Forage quality did not differ significantly between pasture types. Grassy bufferstrips tended to have significantly different vegetation structure from rotational and continuous pastures, because they were not harvested in any way. Grassy bufferstrips developed tall, dense vegetation dominated by reed canarygrass and a few broadleaf species. Both continuous and rotational pastures had shorter, more diverse plant communities with native and non-native wildflowers and legumes.

    Streambanks with grassy bufferstrips were the most stable. Grassy bufferstrips had the least bare ground (17%) on the bank slope, while rotational pastures averaged 24.2% and woody buffer strips and continuous pastures had the most bare soil at 29.9% for woody buffers and 33% for continuous pastures. Instream habitat was as good at rotationally grazed sites as it was at grassy bufferstrips and was better than at either continuous pastures or woody bufferstrips.

    For all types of land management, fish community health was poor to fair. This is typical of this region, which has potential for quality trout fisheries, but has suffered from many years of poor land management. The condition of the watershed upstream from the site accounted for about 90% of the effects we saw at our study sites. However, when these upstream effects are factored out, grassy bufferstrips had the highest quality cold-water fisheries, rated fair versus poor ratings for rotational, continuous, and woody buffer sites. For aquatic insects, which are a food source for trout and an indicator of water quality, rotationally grazed sites were similar to grassy and woody bufferstrips and all three were better than continuously grazed sites.

    Wildlife work was conducted on all sites except woody bufferstrips. We surveyed amphibians, birds, and small mammals and this work is ongoing. Preliminary results suggest that grassy bufferstrips and pastures provide habitat for specific species groups. Amphibians and declining species of grassland birds preferred pasture sites, while small mammals were found primarily in bufferstrips.

    Impacts. Our results suggest that rotational grazing can provide a reasonable compromise between continuous grazing and fencing livestock out of riparian areas. We are working now to educate landowners as well as agency policy makers and field staff on management strategies for riparian areas. Our efforts include field days, public presentations, published papers and articles, and development of a riparian grazing guidelines handbook.


    Riparian areas on livestock farms provide important habitat for wildlife and fish communities and a filter for pollutants. Unrestricted livestock access to streams has long been associated with degradation of these sensitive habitats and the traditional agency response has been to encourage fencing livestock out of riparian corridors. While effective, bufferstrips are seldom used because they take land out of production, restrict access to water for livestock, and require costly maintenance of fencing and vegetation. Intensive rotational grazing is a relatively new option for livestock farmers, which provides environmental as well as economic benefits. Our research suggests that it may be a reasonable compromise between continuous grazing and fencing livestock out of riparian areas altogether. This research compared three management options for riparian areas livestock farms, ungrazed buffer strips, rotational grazing, and continuous grazing, on 21 private farms along trout streams in Southwestern Wisconsin.

    The study involved evaluation of aquatic and terrestrial wildlife community composition and habitat quality as well as forage production and quality. We observed both local land management and larger scale influences on our results. While adjacent land use appears to be a major determining factor in streambank stability and both instream and terrestrial habitat quality, wildlife and fish communities tended to respond more to broad watershed or landscape scale factors than to the local conditions created by the three treatments. Streambank stability and instream habitat were similar for bufferstrips and IRG pastures, but bufferstrips had healthier fish communities with more trout and fewer warm-water fish species. Continuous pastures had poor in-stream habitat quality and poor cold-water fisheries.

    Rotationally grazed pastures produced twice as much forage than continuous pastures. Both rotationally and continuously grazed sites had more diverse plant communities than the grassy buffers. Bufferstrips were dominated by reed canarygrass, while pastures had a diverse mixture of grass species, legumes, and wildflowers. Bufferstrips, of course, were not harvested in any way and the vegetation became tall and rank over the course of the summer. The lack of harvesting in bufferstrips combined with the linear character of this habitat strongly influenced the response of the wildlife community.

    Our results suggest that grazed riparian areas may be more suitable for amphibians and grassland birds than buffer strips, while small mammals were more numerous in bufferstrips than in pastures. Larger numbers of grassland bird species and individuals were observed in both rotational and continuous pastures than in grassy bufferstrips, although the density of birds was higher at bufferstrips. Species diversity and total abundance of grassland birds were greater adjacent to the stream than in upland counts at the same site. Both rotational and continuous pastures attracted more amphibians than bufferstrips. Conversely, many more small mammals, including one species of management concern, were found in bufferstrips than in riparian pastures.

    Among the three treatments, bufferstrips had the healthiest aquatic communities, but did not provide the best habitat for all wildlife communities. Rotational grazing appears to provide a reasonable alternative that protects streambank stability and aquatic habitats and provides good habitat for grassland birds and amphibians. Intensive rotational grazing allows livestock farmers to maximize the productivity of riparian pastures without compromising habitat quality. On a watershed scale, a mixture of rotational pastures and bufferstrips along a stream would provide a diversity of habitats for terrestrial wildlife, protection for aquatic communities, and economically and environmentally sustainable choices for farmers.

    Project objectives:

    The goals of this study were to determine whether IRG can be used as a best management practice (BMP) for riparian areas and to document IRG techniques that are likely to maintain or improve shoreline integrity and reduce water pollution while allowing profitable use of riparian areas by the farmer. Our specific objectives were:

    1. Evaluate rotational grazing management for shoreland corridors and compare with continuously grazed and ungrazed riparian areas in terms of aquatic habitat, terrestrial habitat and forage production.

    2. Develop, in partnership with graziers, guidelines for practical, environmentally sound grazing management of riparian areas.

    3. Convey the developed guidelines to livestock farmers and extension, natural resources, and regulatory agency personnel through field days, publications, and other educational media.

    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.