EVALUATION OF GRASSLANDS-PUNA CHICORY (CICHORIUM-INTYBUS L) IN VARIOUS GRASS MIXTURES UNDER SHEEP GRAZING

Growth of chicory (Cichorium intybus) in mixtures with different compa nion grass species and white clover (Trifolium repens) was examined ov er 4 years in a trial rotationally grazed by sheep. A mixture containi ng red clover (T. pratense) instead of chicory, and ryegrass (Lolium p erenne), was also included. Over summer and autumn, pastures were eith er grazed frequently (every 3-4 weeks) or infrequently (4-6 weeks), an d at other times of the year every 4 weeks. Chicory establishment was high (82% of viable seed sown), with 46 plants/m(2), declining to 15/m (2) by year 4, whereas red clover plant numbers declined from 101/m(2) to 13/m(2). Dry matter (DM) yields of chicory and red clover increase d from Year 1 to Year 3, then declined in Year 4. Over the 4 years, ch icory contributed 34, 80, 85, and 57%, respectively, to green DM yield ; red clover contributed 9, 24, 77, and 13%. Yields of sown grass were inversely related to chicory or red clover yields (P < 0.001, r= 0.82 ), particularly for chicory-based pasture mixtures. Chicory and red cl over both displayed a strong pattern of seasonal growth in response to temperature. This distinct pattern of growth for chicory-based pastur es was greatest for mixtures with tall fescue (Festuca arundinacea) an d prairie grass (Bromus willdenowii), grasses that were low-yielding. In contrast, phalaris (Phalaris aquatica)-chicory pastures had high gr ass growth in all seasons, resulting in the highest total annual DM yi elds and a more even seasonal spread of production. Ryegrass-chicory p astures were intermediate and ryegrass/cocksfoot (Dactylis glomerata)- chicory pastures were lower-yielding. Red clover/ryegrass pastures had a more even seasonal spread of production, through greater winter and lower summer yields, than the chicory-based pastures. Frequent grazin g significantly decreased DM yields of chicory (-19%), red clover (-61 %), and total green herbage (-11%) compared with infrequent grazing, w hereas there was no effect of grazing frequency on plant numbers of ch icory or red clover.