Abstract
106 grasses grown in pots 2.4 × 1.2m at the University Field Station, Valsayn, Trinidad, were cut twice at six weeds of regrowth, in the rainy season. They were analysed for crude protein. They were analysed for crude protein, calcium, phosphorous, magnesium, potassium, sodium, copper, iron, manganese and zinc contents. The ranges for CP, Ca, P, Mg, K and Na (g kg-1 dry matter) were 58-141, 2.8-12.6, 1-3, 0.7-4.4, 1.1-6.4 and 0.16-6.90, respectively, and for Cu, Fe, Mn and Zn (mg kg-1 DM) were 2.2-11.9, 9.90-1473, 63-983 and 11-59n respectively, and for grasses having concentrations for CP, Ca, P, Mg, K, and Na below (g kg-1 DM) 100, 3, 2, 2, 5 and 1 were 68.9, 0.9, 71.7, 41.5, 88.7 and 41.5, respectively. The corresponding values of Cu, Fe, Mn and Zn below (mg kg-1 DM) 10, 100, 100and 30 were 98.1, 0.9, 1.9 and 52.8, respectively. The results are discussed in the light of the requirements of grazing beef and dairy cattle, sheep and goats.