OBJECTIVES: Objective 1 is to determine optimal harvest management strategies, and the feeding and economic value, of modern species and varieties of forage grasses. Objective 2 is to determine the forage potential and optimal management of binary mixtures of modern species and varieties of short- and long-lived grasses with alfalfa. Objective 3 is to determine the animal and economic potential of native warm-season forage mixtures within forage systems.

APPROACH: Objective 1 will be accomplished via a combination of small plot field trials and a feeding trial with lactating dairy cattle. The influence of hay versus simulated rotational grazing harvest regimes on yield, quality, and persistence of diverse varieties of perennial ryegrass and festulolium will be assessed at Grand Rapids, MN, and Chatham, MI. The economic value of direct- and inter-seeded perennial and Italian ryegrass compared to common pasture grasses will be determined at Rosemount, MN, and Marshfield, WI. The yield and persistence benefit of blends versus single varieties of perennial ryegrass and tall fescue will be assessed at Rosemount and Grand Rapids, MN, and Ames, IA. The yield distribution and persistence of various endophyte and tall fescue variety combinations will be determined at Spooner, WI. The milk production potential of good-quality tall fescue hay versus alfalfa hay in total mixed rations for dairy cattle will be determined at St. Paul, MN. Objective 2 will be accomplished via small plot field trials at multiple locations. The influence of varying seeded proportions in binary mixtures of perennial ryegrass versus tall fescue with alfalfa, with and without nitrogen fertilization, on forage yield, quality, and persistence will be assessed at Rosemount and Grand Rapids, MN. The influence of seeding rate of annual versus Italian ryegrass in binary mixtures with alfalfa, seeding-year N fertilization, alfalfa variety, and seeding-year fall harvest management will be assessed at Rosemount and Grand Rapids, MN, and three Wisconsin locations. Objective 3 will be accomplished via a grazing trial with lambs comparing cool- and warm-season grass pastures, with and without legumes included in the mixtures. Alfalfa will be the cool-season pasture legume, whereas a mixture of Illinois bundleflower and Canada milkvetch will be the warm-season pasture legume. Lamb gain per animal and hectare will be determined.

KEYWORDS: forage; alfalfa; pasture; grazing; grass; silage; haylage; hay; native plants; ryegrass; tall fescue; pasture management; legume; establishment; forage quality; illinois bundleflower; forage system; grazing management; forage yield; binary mixture

PROGRESS: 2005/01 TO 2005/12
Objective 1: The second of three studies was initiated at Rosemount, MN, in spring 2005 when perennial ryegrass was no-till seeded into existing plots of several perennial grass sod species. Plots of perennial and Italian ryegrass were direct seeded for comparison. Three or four harvests were obtained during 2005, yield determined, and samples obtained for forage quality analysis. The third of three studies seeded at Grand Rapids, MN, in August 2003 was harvested for its second year in 2005 in MN, and its third year with a collaborator in MI. Festulolium varieties were generally highest yielding, and plots subjected to more frequent defoliation (simulated grazing) higher in quality. Persistence of perennial ryegrass and festulolium entries has been variable, but favorable for most. Objective 2: Experiments conducted in 5 environments (3 in Minnesota, 2 in Quebec) documented that with herbicide sod suppression and seeding-year N fertilization, Kura clover can be consistently established in existing perennial grass sods via sod-seeding. Though Kura clover contributed little to sward yield during the establishment year, its presence increased to attain higher yields than white or red clover after two winters. Also, N fertilization during the sod-seeding year increased renovation-year yields without harming clover establishment. Objective 3: We evaluated the effects of wheel traffic 2 days (haylage simulation) versus 5 days (hay simulation) after each harvest on yield and stand of alfalfa varieties. Averaged over varieties, wheel traffic 2 vs. 5 days after harvest reduced 3-yr cumulative alfalfa yields by 13 and 29%, respectively. Varieties varied, however, in their response to wheel traffic. When trafficked 2 days after each harvest, yield reductions over 3 yr ranged from 5 to 18%. Similarly, when trafficked 5 days after each harvest, yield reductions ranged from 21 to 37%. Yield reductions are due to a combination of soil compaction and shoot breakage. After 3 yr of 5-day traffic and 3 winters, alfalfa variety stands ranged from 62 to 20%. Objective 4: We evaluated the effects of maturity at harvest, cutting height, and N fertilization on forage yield, forage quality, and persistence of Illinois bundleflower at 4 locations. Its forage quality was greatest at early flower in mid-July. Fiber values increased while CP decreased at late pod in mid-August. In vitro digestibility decreased from early flower to late pod. Its low in vitro digestibility suggests anti-quality components may exist. Increasing cutting height from 15 to 35 cm decreased ADF and NDF and increased digestibility and CP. We documented that Illinois bundleflower can provide good quality summer forage in the upper Midwestern USA, but its persistence in monoculture is limited, especially in harsh winters.

IMPACT: 2005/01 TO 2005/12
Results of this research provide evidence for the forage potential of several plant species not currently used extensively in Minnesota, and information for how to establish and manage them. When used as forages on farms, these species should improve the profitability of perennial, environmentally sound, forage-based systems.

PUBLICATIONS (not previously reported): 2005/01 TO 2005/12
1. Cuomo, G.J., M.V. Rudstrom, D.G. Johnson, J.E. Anderson, A. Singh, P.R. Peterson, and C.C. Sheaffer. 2005. Nitrogen fertilization impacts on stand and forage mass of cool-season grass-legume pastures. Online. Forage and Grazinglands doi:10.1094/FG-2005-0831-01-RS.
2. Cuomo, G.J., M.V. Rudstrom, P.R. Peterson, D.J. Johnson, A. Singh, and C.C. Sheaffer. 2005. Initiation date and nitrogen rate for stockpiling smooth bromegrass in the north central USA. Agron. J. 97: 1194-1201.
3. Fischbach, J.A., P.R. Peterson, N.J. Ehlke, D.L. Wyse, and C.C. Sheaffer. 2005. Illinois bundleflower forage potential in the upper midwestern USA: II. Forage quality. Agron. J. 97: 895-903. (reported as "in press" last year).
4. Fischbach, J.A., P.R. Peterson, C.C. Sheaffer, N.J. Ehlke, J. Byun, and D.L. Wyse. 2005. Illinois bundleflower forage potential in the upper midwestern USA: I. Yield, regrowth, and persistence. Agron. J. 97: 886-894. (reported as "in press" last year)
5. Laberge, G., P. Seguin, P.R. Peterson, C.C. Sheaffer, and N.J. Ehlke. 2005. Forage yield and species composition in years following Kura clover sod-seeding into grass swards. Agron. J. 97: 1352-1360.
6. Laberge, G., P. Seguin, P.R. Peterson, C.C. Sheaffer, N.J. Ehlke, G.J. Cuomo, and R.D. Mathison. 2005. Establishment of kura clover no-tilled into grass pastures with herbicide sod suppression and nitrogen fertilization. Agron. J. 97: 250-256. (reported as "in press" last year)
7. Peterson, P.R., P. Seguin, G. Laberge, and C.C. Sheaffer. 2005. Renovation-year forage quality of grass pastures sod-drilled with Kura clover. p.171. In Utilisation of grazed grass in temperature animal systems, Proc. satellite workshop XX Int. Grassl. Congr. Cork, Ireland. 3-6 July 2005.

PROJECT CONTACT:
Name: Peterson, P. R.
Phone: 612-625-3747
Fax: 612-625-1268
Email: peter072@umn.edu