HERBAGE AND BEEF PRODUCTIVITY OF FERTILIZED PASTURES IN NORTHERN ONTARIO

The productivity of 2 fertilized sown pasture swards and of a 30-year-old pasture sod was evaluated under rotational and continuous grazing in 1956–62.The application of NP fertilizer (448 kg 11–48–0/ha every 3 years with 112 kg ammonium sulphate in the other years) gave the highest yields of DM and of beef, followed by the P treatment (1120 kg superphosphate/ha). Beef production showed only small responses to either the type of pasture sward, or the method of grazing. Seasonal distribution of beef production was slightly more even on the old sod. For the peak period of June-July, 68% of the gain was made on the old sod against 74% on the cultivated swards under rotational grazing and 79% under continuous grazing. DM/gain ratios were generally higher in wet summers than in dry ones. Conversely, estimated DM digestibility was lowest in wet summers.