Pattern of grassland sward yielding when abandoned or grazed by small ruminants in K odzko Valley

Research was performed on grassland in K odzko Valley of the Sudety Mountains on the altitude of 550 m. A paddock of 2.4 ha was fenced on natural grassland which had been fallow for more than 10 years and small ruminants grazed it for 3 years on an all day basis - the stocking rate was from 0.42 LU (spring season) to 0.75 LU (summer-autumn season) where sheep to llamas ratio was as 3 to 1. No fertilizer application was performed. The yielding of grazed and fallow swards were compared in the 4-th year. Data were collected from 9 test plots on the grazed pasture and 9 plots on the fallow grassland. The height of the sward, its yield and basic chemical composition was evaluated 4 times during the growing season, starting in April and ending at the beginning of October. Grazed pasture yielded for the entire growing season 4.4 t of DM while fallow grassland 5.9 t of DM per ha. Daily production of DM per ha till the end of April, May - June, June-July and August-September periods for grazed pasture were as follows: 11, 35, 24 and 18 kg of DM while for fallows grassland: 25, 51, 29 and 17 kg DM. Despite a similar pattern of DM yielding during the vegetation season DM yield per 1 cm of sward height was the effect of grazing. The yield of DM per 1 cm of sward height was lower till the end of April, in June-July periods respectively by: 19 and 33% on the grazed pasture when compared to the fallow while in August-September it was higher by 99%.