Submitted to: Range Management Meeting Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: September 16, 2004
Publication Date: February 6, 2005
Citation: Klement, K.D., Sanderson, M.A., Goslee, S.C., Soder, K.J. 2005. The Hidden Diversity of Pastures [abstract]. Range Management Meeting Proceedings. p.195. CDROM. Interpretive Summary: An interpretive summary is not required.
Technical Abstract: Maintaining desirable forage species in grazed pastures for multiple years is challenging as less favorable plant species increase in soil seedbanks and affect the desired composition of the pasture. Our objective was to determine species richness of soil seedbanks from pastures seeded to four forage mixtures. Treatments were 2-species (orchardgrass, white clover); 3-species (orchardgrass, white clover, and chicory); 6-species (orchardgrass, chicory, Kentucky bluegrass, tall fescue, red clover, birdsfood trefoil); and 9-species (6-species mix, white clover, perennial ryegrass and alfalfa). Treatments were twice-replicated on 1-ha paddocks. Soil cores were taken from each of eight paddocks in April 2002, 2003, 2004 and October 2002, 2003. Weekly seed germination was assessed for 18 months in the greenhouse under ambient temperature and light conditions. At each sampling, aboveground species composition was >50% seeded species, whereas <5% seeded species germinated from soil seedbanks. Of the nine seeded species, only white clover germinated frequently in all treatments. Annual forbs contributed the greatest total seed density by functional group with least abundance (71%) in April 2002 and greatest (92%) in October 2003. Total seed density was consistently greater in the 2-species treatment with >11,000 seeds m-2 in each of the first four collection periods and >5,000 seeds m-2 after only three months in April 2004. Also, October samples had larger total seed densities than April samples for all treatments. Results indicate pasture mixes of three or more preferred forage species had less total germinable seeds and proportionately less undesirable species in soil seedbanks than the 2-species mix.