Determining Timely Entry and Exit of Livestock in Rangelands Using Bromus tomentellus Phenological Stages (Case Study: Goorab Rangeland of Isfahan)

In the rangelands of Iran, the lack of appropriate grazing management is one of the major problems ultimately leading to untimely and excessive grazing intensity of forage. Accordingly, most of the rangelands show a retrogression trend and poor conditions. In forage species, phenological stage is one of the most important criteria for range management. Bromus tomentellus species is an important range species for forage production controlling soil erosion. In order todetermine the timely entry and exit of livestock in rangelands based on phenological stages of B. tomentellus, this study was conducted in Goorab rangeland, Fereydoun Shahr, Iran during four years (2007-2010). In this research, ten plant bases of B. tomentellus were selected and their phonological stages were recorded in a 7-day interval period. At the same time, meteorological data were collected from meteorological station adjacent to the study site. According to the occurrence of biological phenomena in the different years of study (wet conditions in 2007, severe droughts in 2008 and normal years in 2009 and 2010) and also based on plant growth stage in the 4 year study, it was concluded that 30th April and 31th May were suggested as the best time for livestock to enter and exit from the rangeland, respectively.