Eleocharis palustris
 
Creeping Spike-Rush

Spikelet, Sterile Scales Pulled Back, Side A

Hudson Bay Regional Park
22-June-2015

The sterile scales at the base of the spikelet have been pulled back to reveal the absence of a flower.

Eleocharis palustris is a member of the Eleocharis palustris complex. This complex contains a number of difficult to distinguish species.  Flora of North America (FNA) recognizes seven:

bulletE. palustris
bulletE. mamillata
bulletE. macrostachya
bulletE. erythropoda
bulletE. uniglumis
bulletE. kamtschatica (coastal species, not found and not expected to be found in SK)
bulletE. ambigens (coastal species, not found and not expected to be found in SK

The following characters are used in the portion of the FNA key which pertains to the E. palustris complex:

bulletCulms Compressed/Terete
bulletDistal Leaf Sheath Apex with/without Distinct, Abrupt Tooth
bullet# Floral Scales per mm of Rachilla
bulletProximal Scale Clasps How Much of Culm
bulletProportion Subproximal Scales Without Flower
bulletFlattened Floral Scale Dimensions
bullet# of Perianth Bristles
bulletPerianth Bristles Relative Size
bulletAchene Apex with/without Distinct Neck
bulletAchene Surface
bulletTubercle Dimensions
bulletTubercle Size Compared to Achene
bulletTubercle Height to Width
bulletTubercle Surface

The character states (of the above characters) for all members of the E. palustris complex are found in this table.  These character states are taken from the species descriptions (not the key) in Flora of North America.

The portion of the FNA key which pertains to the E. palustris complex is found hereSpecies not found in Saskatchewan are noted.