FLORA OF ICELAND elements: Carex mackenziei, Mackenzie's Sedge, Skriðstör

Carex mackenziei; The Mackenzie's Sedge is a low to medium sedge (15-40cm) on brackish soils.
  The leaves are under 4mm wide. They rise from stolons but then tend to form tuft-like structures.
  The inflorescence is characterized by a top spike that has many male flowers at the bottom of the spike and female flowers on top. The spikes below are smaller and mainly bearing female flowers. Quite characteristic is the "naked" stretch under the developing fruits of the top spike where the male flowers were positioned. As such it resembles Carex lachenalii (see note below). The female flowers have two stigmas. The utricles have a short beak. The bracts below though have a long pointed apex, much overlapping the utricles.
  It can be found on salt marshes all along the Icelandic coast except for southern regions.
  It is a member of the sedge family (Cyperaceae). The Icelandic name of this species is Skriðstör.

It is sometimes been said that it resembles the silvery sedge (Carex canescens). The two are very different in that the silvery sedge is much lighter and misses the large male-section at the bottom of the top spike even as it does have male flowers on the bottom of (all) spikes. The Mackenzie's Sedge actually resembles the Hare's-foot Sedge (Carex lachenalii) much more. One identifying difference is that the Mackenzie's Sedge has more female spikes beneath the top of the stem, i.e. the spikes are less condensed into the top part of the culm. The culms of the Mackenzie's Sedge are much more straight than the (nodding) culms of the Hare's-foot Sedge. For information on Carex lachenalii see here. Finally it should be noted to that the Mackenzie's Sedge grows on saline soils, the Hare's-foot Sedge never grows on these soils.