INFLUENCE OF TIME AND FREQUENCY OF HARVESTS ON PRODUCTIVITY AND CHEMICAL COMPOSITION OF FERTILIZED AND UNFERTILIZED AWNED SEDGE
Awned sedge (Carex atherodes Spreng.) fertilized with 224 kg/ha 16-20-0 plus 112 kg/ha 0-0-60 in shallow water over clay soil in May 1972 and on wet ground on the same plots in October 1972 was not different from controls in yield or chemical composition in 1972 or 1973. All yields in 1973 were less than from corresponding treatments on the same plots in 1972. Plots mowed once and twice each year averaged about 7,500 kg/ha forage, 620 kg/ha protein per year compared with 3,000 kg/ha forage and 520 kg/ha protein for six mowings from late May or early June to September. The latter, however, produced only about one third as much forage in 1973 as in 1972, though its chemical quality either did not decline or tended to increase during the season. Protein and P percentage in first cuttings declined from May to September. There was little change in Ca. Near-maximum fibre content occurred by late June in undisturbed sedge. Analytical data compared favorably with those reported for upland or meadow grasses. On balance, two mowings per year seemed optimum regarding yield and chemical composition. More frequent cuttings soon weakened the stand and therefore apparently would be desirable only as preparation for introduction of other hay, or other cover for wildlife or for elimination of lake margin growth.