Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Plants, Soils, and Climate

Committee Chair(s)

W. H. Bennett


W. H. Bennett


Wesley Keller


R. W. Peake


Bliss Crandall


The chief aim of pasture research is to discover means of providing the largest possible amount of highly nutritious forage at the time the animal requires it. Throughout the grazing season animal herbage requirements are relatively constant, while herbage production from pastures usually is quite variable. Several practices have been employed in an attempt to obtain more uniform seasonal production, and overcome periods of feed surplus and feed shortage during the grazing season. One such practice has been to seed pastures comprised of several species. This is based on the observation that forage species differ in their requirements, and make maximum growth at different times of the year. Thus, it has been suggested, if the correct combination of species is obtained, production will be uniform throughout the season. However, uniform production has not generally been realized, and most mixtures follow similar patterns of production, determined by factors other than species composition. This observation, brings up the question of whether it has been correct to assume that each species would maintain its individual characteristics in a mixture. It seems reasonable that one species would affect the growth habit of others with which it is associated. In the work reported herein, a comparison was made of the seasonal frowth and yield of 3 grass species when grown alone and when grown in mixtures. The mixtures included all combinations of the three species with each other, and with white Dutch clover. The total yields of the mixtures were also compared for seasonal yield fluctuations. Nitrogen determinations were made on most of the separated species. Some of the literature pertaining to problems involved in obtaining uniform seasonal production was reviewed. The work was done at the Dominion Experimental Station, Lethbridge, Alberta, Canada, in 1952 and 1953.