Seasonal Distribution of Forage Yield and Winter Hardiness of Grasses from Diverse Latitudinal Origins Harvested Four Times Per Year in Southcentral Alaska
Leslie J. Klebesadel, Emeritus Professor of Agronomy
Agricultural and Forestry Experiment Station, Palmer, Alaska
Bulletin 90; June 1992 (11 pages)
Summary
Objectives were to compare under intensive utilization (high fertility, four harvests per year, supplemental irrigation) total forage production, seasonal distribution, and winter hardiness among 12 subarcticadapted and three midtemperateadapted strains of Kentucky bluegrass (Poa pratensis L.); four subarcticadapted strains of red fescue (Festuca rubra L.); two midtemperateadapted cultivars of red fescue, one of chewings fescue (F. rubra var. commutata Gaud.) and one of hard fescue (F. ovina var. duriuscula [L.] Koch); and three tallgrowing, northernadapted forage grass cultivars: Polar hybrid bromegrass (predominantly Bromus inermis Leyss. x B. pumpellianus Scribn.), Garrison creeping foxtail (Alopecurus arundinaceus Poir.), and Engmo timothy (Phleum pratense L.).
The study was conducted over three years at the Matanuska Research Farm (61.6°N) near Palmer in subarctic, southcentral Alaska. Mean harvest dates during the two years were 11 June, 9 July, 14 August, and 25 September.
*The seven midtemperateadapted cultivars of fescue and Kentucky bluegrass were inadequately winter-hardy, producing low yields during the first year and none during the second year; the sole exceptions were
Troy Kentucky bluegrass and Durar hard fescue which produced some forage during the second harvest year, but those yields were very low also.
*Of the tall-growing grasses, Polar bromegrass and Garrison creeping foxtail were more winter-hardy than Engmo timothy; the latter sustained severe winter injury during the second winter. Polar bromegrass showed slightly poorer winter survival than the most winter-hardy strains of Kentucky bluegrass.
*Considerable differences in winter hardiness were noted among the subarcticadapted strains of Kentucky bluegrass and red fescue, and the best of those produced higher yields with more even distribution than the commonly used taller-growing forage grasses.
*Yield distribution of Polar was uneven; it produced high yields in the first and third harvests, but was the least productive of all northern-adapted grasses in the second (early July) harvests.
*All grasses were low yielding at the fourth harvest (late September) in both years, despite the final growth period being longer than the others.
*The winter-hardy subarcticadapted strains of Kentucky bluegrass and red fescue produced evenly distributed, high yields of forage under intensive utilization.