The Asir Mountains in the southwest of the country, and most of the western highlands of Yemen, support a distinct flora which has affinities with parts of East Africa. The highest parts are clothed with cloud forests, southwestern Arabian montane woodlands which includes, on north-facing slopes, Juniperus procera and Euryops arabicus, draped with the lichen Usnea articulata, and on south-facing slopes, dwarf shrubs such as Rubus petitianus, Rosa abyssinica, Alchemilla crytantha, Senecio and Helichrysum abyssinicum, with Aloe sabae and Euphorbia in the driest locations. Lower down, below about 2,500 m (8,200 ft), there is evergreen woodland and scrub dominated by Olea europaea subsp. cuspidata and Tarchonanthus camphoratus.