To study the effects of sheep (Ovis aries L.) rates and grazing duration on weed ‎control and saffron biomass, a field experiment was conducted during the year 2006, in a ‎saffron (Crocus sativus L.) field located in Boshrooyeh (33° North latitude, 57° East ‎longitude), Razavi Khorasan, Iran. A split plot design based on randomized complete block ‎with three replications was used. The treatments comprised three sheep rates, 200, 400 and ‎‎750 sheeps per hectare allocated in main plots and three grazing durations, 2, 3 and 4 days ‎‎(8 hours per day) allocated in subplots. The factors studied consisted of above ground dry ‎weight of common grasses (Hordeum spontaneum, Lolium rigidum), broadleaf weeds ‎‎(Cardaria draba and Carduus pycnocephalus) and dry weight above ground biomass of ‎saffron. Results showed that sheep rates had significant effects on above ground dry ‎weight of grass and broadleaf weeds. Duration of grazing had a significant effect on ‎saffron above ground biomass. With increasing sheep rates from 200 to 400 per ha, dry ‎weight of weeds (grass and broadleaf) decreased significantly. In the highest rate of sheep ‎‎(750 per ha) with increasing the duration of grazing from 2 to 4 days, dry weight of saffron ‎leaves decreased significantly. Our results suggest the idea that grazing with 400 sheep per ‎hectare for duration of 3 days is required for acceptable control of weeds in saffron field ‎without any significant reduction in above ground saffron biomass.‎

To study the effects of sheep (Ovis aries L.) rates and grazing duration on weed ‎control and saffron biomass, a field experiment was conducted during the year 2006, in a ‎saffron (Crocus sativus L.) field located in Boshrooyeh (33° North latitude, 57° East ‎longitude), Razavi Khorasan, Iran. A split plot design based on randomized complete block ‎with three replications was used. The treatments comprised three sheep rates, 200, 400 and ‎‎750 sheeps per hectare allocated in main plots and three grazing durations, 2, 3 and 4 days ‎‎(8 hours per day) allocated in subplots. The factors studied consisted of above ground dry ‎weight of common grasses (Hordeum spontaneum, Lolium rigidum), broadleaf weeds ‎‎(Cardaria draba and Carduus pycnocephalus) and dry weight above ground biomass of ‎saffron. Results showed that sheep rates had significant effects on above ground dry ‎weight of grass and broadleaf weeds. Duration of grazing had a significant effect on ‎saffron above ground biomass. With increasing sheep rates from 200 to 400 per ha, dry ‎weight of weeds (grass and broadleaf) decreased significantly. In the highest rate of sheep ‎‎(750 per ha) with increasing the duration of grazing from 2 to 4 days, dry weight of saffron ‎leaves decreased significantly. Our results suggest the idea that grazing with 400 sheep per ‎hectare for duration of 3 days is required for acceptable control of weeds in saffron field ‎without any significant reduction in above ground saffron biomass.‎

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