Abstract
An experiment was undertaken to investigate the relations of the heading property of various species to the competition in the mixed swards of tropical grasses. Three prostrate type grasses, bahiagrass (cv. FC 33195), kikuyugrass (cv. Whittet) and pangolagrass (cv. Florida) were grown under field conditions in the experimental plots designed so as to obtain specific competitions between two and among three grasses and also the conditions without specific competition. Grasses were grown under usual cultural practice with or without cutting treatment. Results obtained were summarized as follows.
1. In the no cutting plots, pangolagrass which spreaded most widely and was the tallest, produced more heading tillers than bahiagrass and revealed the highest competitive ability in lst year. Bahiagrass, its heading tiller numbers being less than pangolagrass, was suppressed more severely by pangolagrass than by kikuyugrass which spreaded more than bahiagrass. The hea ding of kikuyugrass was not observed.
The over-wintering ability was the highest in bahiagrass. This might relate to that heading rate of bahiagrass was generally higher than that of pangolagrass in 2nd year. Owing to its vigorous heading, bahiagrass competed with pangolagrass more favourably in 2nd year than in 1st year. Kikuyugrass, though it spreaded nearly as much as pangolagrass, competed less favourably with pangolagrass than with bahiagrass, realating to that kikuyugrass produced no heading tiller also in 2nd year.
2. In the cutting plots, the heading was suppressed more severely in pangolagrass than in bahiagrass throughout two years. And also, the cutting treatment lowered the competitive ability of pangolagrass more than that of the other two species.
3. Thus, the heading of the grasses had some relations to the competitive ability of each grass. From this, it was assumed that the botanical composition in mixed swards of tropical grasses might be controlled by combining appropriate species and cutting back properly in comformity with the heading property of each grass.
