The highlands themselves are divided into three distinct ecoregions, distinguished by elevation. The Ethiopian montane forests lie between 1,100 and 1,800 meters elevation, above the lowland grasslands and savannas, and extends to areas of similar habitat in Eritrea, Sudan, and Djibouti. This woodland belt has several natural plant communities, but has mostly been heavily grazed and converted to agricultural use now. "Kolla", is an open woodland found at lower elevations, and dominated by species of "Terminalia", "Commiphora", "Boswellia", and "Acacia". "Weyna dega" is a woodland found in moister and higher locations, dominated by the conifers "Afrocarpus gracilior" and "Juniperus procera". The lower portion of the Harenna Forest is a distinct woodland community, with an open canopy of "Warburgia ugandensis", "Croton macrostachyus", and "Syzygium guineense", and "Afrocarpus gracilior", with wild coffee ("Coffea arabica") as the dominant understory shrub. The southwesterly winds bring rainfall from May to October with moisture from the Red Sea coming in from the east year round.