Cool Season Perennial Grass Evaluations
A cool-season perennial grass trial was initiated on October 4, 1996 at the NF Headquarters farm, in collaboration with Dr. Larry Redmon of Oklahoma State University. The establishment year conditions were characterized by intermittent wet periods during the fall and spring followed by extremely dry conditions during the summer of 1997.
The late fall planting date and cold temperatures during winter and early spring contributed to delayed forage harvest in the spring of 1997. Clippings were made in April, May, June and December (see table). Plots were clipped at a 3-inch stubble height to simulate rotational grazing. Dried forage samples were ground and a laboratory analysis performed to estimate crude protein (CP).
Data for dry matter forage production at each clipping date and average percent CP are presented in the table below. All of the grass species contained good to excellent CP values at each sample date. CP percentages were highest in early May and lowest in the April clipping.
Matua prairiegrass and Nui perennial ryegrass produced the earliest forage and the most total forage for the year. However, both suffered from drought during the summer and stands were extremely thin by the December clipping for both species. This verifies previous testing in Oklahoma that Matua probably should be managed as a re-seeding annual such as annual ryegrass. It should be allowed to flower and set seed each year to produce the next year's crop. An excellent stand of Paiute orchardgrass was obtained in the plots. It also produced good early forage but by December there were very few mature plants remaining in the stand.
Dovey tall fescue looks promising as an endophyte-free variety. It produced significantly earlier and more total forage than the Kentucky 31 endophyte-infected variety in this establishment year. Dovey also exhibited good drought tolerance during the summer and maintained better stands than Kentucky 31 by December.
The wheatgrasses, smooth bromegrass, meadow brome and Russian wildrye were slower to develop and did not produce nearly as much initial forage as the grasses cited above. However, these grasses as a group would appear to have potential for this region because of their drought tolerance. All maintained good to excellent CP levels and stands throughout the entire year.
This is preliminary data and should be used with caution. Our data closely coincides with previous testing by Dr. Redmon at other Oklahoma sites. However, subsequent harvesting and sampling over several years will provide a better indication of which of these cool-season perennial grass species has the best potential for this region of the country.