The Yezidis have traditionally divided themselves into two groups, according to their life-styles: the sedentary "people of the villages" (Ahi al-hadr) and the nomadic "people of the tents" (Ahl al-wabar). The sedentary Yezidis live in villages of about sixty houses. The houses are made of clay, stone, or raw brick; covered with white plaster; and divided into three main rooms. The roof is supported by wooden pillars. The nomadic Yezidis live in low tents, firmly lashed to the ground to resist the wind—each housing about five people. After the annexation of Armenia by the former USSR, the nomads were encouraged to settle in villages, and the majority of Transcaucasian Yezidis have by now abandoned the nomadic way of life. Some, however, continue to migrate between summer and winter villages. The first Yezidi collective farm in Soviet Armenia was established in 1928; nevertheless, in 1936 most of the farms near Mt. Aragats were still cultivated by individuals.