Flora and vegetation of the Ashk Island (Urumia National Park) has studied and determined during 1986-1987 in continuing author’s previous floristic studies in 1983.
Total 198 species belonging 149 genera of 46 families including 1% Gymnosperms, 14% Monocots and 85% of Divots determined as the flora of this island. Among known species 51.8% of annuals, 3% of biennials, 34.9% of herbaceous or under shrub perennials and 10. 3% of woody species recognized in floristic composition.
Nearly all species are Irano-Touranian clement and halophytes or xerophytes were dominant.
43.4% of all species belong to the families Compositae, Gramineae, Leguminosae, Labiatae, Caryophyllaceae and Chenopodiaceae; and all other families, each including less than 10 species.
Among herbaceous or undershrubs, the genera Artemisia, Aegilops, Senecio, Salsola and those of woody species, Pistacia and Rhombus were the most frequent and dominant. The following vegetational types were recognized:
1) The shore-line vegetation type, mainly comprised of Frankenia spp.; Suaeda spp. and Limonium spp.
2) The main ground cover, comprised of various pure or associate species of the genera Artemisia, Salsola, Dianthus, Crucianella, Carex etc.
3) Trees and shrubs, which well distributed in valleies and slopes, comprised of two main species, Pistacia atlantics and Rhombus pallasii and in some area accompanied by either Celtis, Amygdalus, Berberis and species.
4) The grass cover of top hills and highlands comprised mainly of Poa, Hordeum, Bromus and Aegilops.