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Species Image Gallery (opens in a new window) |
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| THE SEDGE FAMILY | |||||||||
| The sedge family is widespread around
the world, but these plants are usually found in damp habitats in subarctic
to temperate regions. The sedge family is very large, with approximately
5,315 species! There is a lot of variability within the family, but in general,
they are all perennial rhizomatous herbs. The stems are solid and are frequently
three sided. The leaves are in three vertical rows. The basal sheath of
the leaves is closed. The leaves are linear and have parallel venation typical
of the monocots. The inflorescences vary greatly among genera. In general,
flowers are in spikelets which are arranged into spikes, racemes, panicles
and umbel-like clusters. In each spikelet there are bracts, usually at least
one per flower. The flowers are reduced, meaning that they do not have obvious
sepals and petals. The sepals and petals, if present, are often bristles,
scales or hairs. There are three stamens and two or three carpels. The flowers
may have both male and female parts or only one of the two. In one of the
main genera, Carex, the ovary is enclosed in a sac-like bract called
the perigynium. The fruits are achenes and are lens-shaped or triangular. The sedges are an ecologically important family in Saskatchewan. Saskatchewan has 149 species belonging to the Cyperaceae. | |||||||||
| DWARF SPIKERUSH | |||||||||
| LATIN NAME: Eleocharis parvula | |||||||||
| WHAT DOES IT LOOK LIKE? | |||||||||
| Dwarf spikerush is a very small, mat-forming species. The stems are thread-like and round in cross section. There are no blade-bearing leaves. The leaf sheaths are short and membranous. The spikelet is solitary at the end of the stem and contains two to nine flowers and about six to ten floral scales. The lowest scale is always empty. The scales can be straw-coloured or green or brown. There are usually six perianth bristles. The styles are three branched. The achene is egg-shaped with a small swelling at the base of the style. | |||||||||
| WHERE DOES IT GROW? | |||||||||
| Dwarf spikerush grows on moist shores of saline lakes. | |||||||||
| WHERE IS IT FOUND IN SASKATCHEWAN? | |||||||||
| This species grows in southwestern Saskatchewan in the Moist Mixed Grassland and Mixed Grassland ecoregions. | |||||||||
| WHY IS IT RARE? | |||||||||
| Dwarf spikerush is threatened in Saskatchewan because it is extremely rare and is limited to one general region of the province. This species is usually locally numerous but within limited areas. Possible threats have been identified for this species. Dwarf spikerush has not been reported elsewhere in Canada and the Saskatchewan populations may represent a northern range extension. | |||||||||
| HOW TO IDENTIFY DWARF SPIKERUSH | |||||||||
| * Are the stems less than 10 cm tall and mat-forming? * Is the spikelet terminal and solitary? * Do the flowers have a three-branched stigma? * Did you find it in southwestern Saskatchewan? | |||||||||
| If you answered yes to all of these questions, you may have found dwarf spikerush! | |||||||||
