Dates are naturally wind pollinated, but in both traditional oasis horticulture and in the modern commercial orchards they are entirely pollinated manually. Natural pollination occurs with about an equal number of male and female plants. However, with assistance, one male can pollinate up to 100 females. Since the males are of value only as pollinators, this allows the growers to use their resources for many more fruit-producing female plants. Some growers do not even maintain any male plants, as male flowers become available at local markets at pollination time. Manual pollination is done by skilled labourers on ladders, or by use of a wind machine. In some areas such as Iraq the pollinator climbs the tree using a special climbing tool that wraps around the tree trunk and the climber's back (called تبلية in Arabic) to keep him attached to the trunk while climbing.