Renovation and Management Effects on Pasture Productivity Under Rotational Grazing

Authors: Brink, Geoffrey; JACKSON, RANDALL - UNIVERSITY OF WISCONSIN

Submitted to: American Forage and Grassland Council Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 9/19/2007
Publication Date: 1/26/2008
Citation: Brink, G.E., Jackson, R.D. 2008. Renovation and Management Effects on Pasture Productivity Under Rotational Grazing [abstract]. American Forage and Grassland Council Conference Proceedings. Paper No. 1827. 2007 CDROM.

Interpretive Summary:

Technical Abstract: Adapted, perennial grasses with improved yield or persistence are available for pasture renovation, but grazers must consider how productive and persistent the new grass will be compared to their existing grasses under their current management. Our objective was to compare the productivity and persistence of introduced grasses with existing grasses, and to determine the relative contribution of adjacent vegetation to plant communities in renovated pastures. The experiment is being conducted on five Wisconsin farms that utilize management-intensive rotational grazing for dairy or beef production. Within a paddock on each farm, one half of a 2-acre block was sprayed with glyphosate to kill existing vegetation in fall, 2005. In spring, 2006, the sprayed block was disked and seeded with a mixture of orchardgrass (Dactylis glomerata L.) and meadow fescue (Festuca pratensis Huds.). After establishment, both the renovated and existing grasses were managed either by the producer according to his/her typical goals or according to research standards for optimum production. Species composition, and forage yield and quality within each treatment were measured in the spring, summer, and fall of each year. Each producer estimated yield before and after every grazing event using a rising plate meter. In the spring, 2007, renovated plots were populated by orchardgrass (59%), meadow fescue (16%), bluegrass (Poa pratensis L.; 4%), white clover (Trifolium repens L.; 7%), quackgrass [Elymus repens (L.) Gould; 4%], and weeds (10%); quackgrass and weeds were generally more prevalent in the block managed by producers. Depending on the farm, existing pastures were dominated by orchardgrass, bluegrass, or quackgrass, except on one farm where meadow fescue was the dominant grass. On four of five farms, annual yield was improved by renovation under producer and research management, but renovation did not improve forage quality over existing pastures.