Salix-retusa_22

Description:

Salix retusaRetuse-leaved WillowSlo.: topolistna vrbaAlmost ripe fruits, some are already oppening.Dat.: Aug. 12. 2013Lat.: 46.44293 Long.: 13.64503Code: Bot_742/2013_IMG3991andDat.: Aug. 22. 2013Lat.: 46.44178 Long.: 13.64405Code: Bot_745/2013_DSC7572(Fig.: #22)Habitat: Upland stony grass land, pasture, among large calcareous boulders, modestly eastward inclined terrain, full sun, exposed to precipitations, average precipitations ~3.000 mm/year, average temperature 1-2 deg C, elevation 1.970 m (6.450 feet), alpine phytogeographical region.Substratum: soil.Place: Mangart flats west of Mt. Margart, 2.677 m (8.783 feet) near Mangart Alpine road, East Julian Alps, Posoje, Slovenia ECComment: Salix retusa is a common high-elevation plant in Slovenia. It is often called 'The smallest tree of the world'. However, in higher elevations of the Julian Alps four Salix species grow, which could compete for this title. Actually Salix retusa is even not the lowest one. These trees have their small but strong trunks and branches made of true wood with very dense growth rings. Some plants can be very old. But they never grow tall but stay low on ground. Salix herbacea even hides its branches underground. Only its leaves can be seen giving no impression that they belong to a tree. This is of cause a way of accommodation to very harsh living conditions at high altitudes. Salix retusa can sometimes be quite of significant size in Julian Alps and can cover up to one m2 (10 square feet) of ground; however it is never taller than a few cm.Ref.:(1) A.Martini et all., Mala Flora Slovenije, Tehnina Zaloba Slovenije (2007), p 467. (2) K.Lauber and G.Wagner, Flora Helvetica, 5. Auflage, Haupt (2012), p 412.