Investigation on ecological characteristics of Astragalus squarrosus in Kashan rangelands

Understanding ecological needs of range species is of utmost importance for range managers in conservation and utilization of rangeland ecosystems. The current research was conducted to find out ecological characteristics of Astragalus squarrosus in Kashan. In each study area, soil sampling was performed at depths of 0-30 and 30-60 cm along four transects. Vegetation sampling was done in three phonological stages of vegetative growth, flowering and seed ripening. Soil studies of the mentioned species showed that it mainly grew in soils with sandy loam to loamy sand textures, EC of 0/4 -4/2 ds/m and pH of 7/49 -8/17. According to the results of the vegetation studies, average of the current yield was 78/3 kg/ha and 1322/9 species per hectare was estimated as average of the density of A. squarrosus. Forage quality analysis at three phonological stages of vegetative growth, flowering and seed ripening showed that the amount of CP and OC were reduced up to 3.6% and 0/82 respectively. Decrease of DMD and ME and increase of ADF values at seed ripening stage was associated with a considerable decrease in palatability and subsequently forage quality.