FLORA OF ICELAND elements: Juncus castaneus, Chestnut Rush, Dökkasef

Juncus castaneus; The Chestnut rush is a rather rare species on Iceland. I photographed this plant near Akureyri (where it isn't supposed to grow!). It seems the species is most common in eastern Iceland and in the North-Western fjords. The stems sprout from rhizomes every few centimeters apart. A few leaves on the stem are flat grass-like blades. A rather similar specie (J. biglumis) has no stem-leaves. Characteristic for this species is an inflorescence (only one or two flower clusters) embraced by a short bract (about the length of the inflorescence) and a longer bract (about twice the length of the inflorescence)- see notes on subspecies. The Icelandic name of this species is Dökkasef.
Note: On Iceland 2 subspecies have been found in different regions. The subspecies castaneus is found in the east of Iceland, whereas the subspecies leucochlamys is found mainly in the west fjords. They differ in that the nominate has 1 to 3 dark and unstalked or short-stalked. The lowest bract is short. Ssp Leucochlamys has several pale long-stalked heads (the seeds are black in both ssp!) and the lowest bract is short. The photo shown is one of the subspecies castaneus. The subspecies leucoclamys is regarded by several experts as a single species (Juncus leucochlamys). It is a member of the rush family (Juncaceae).