Scirpus

Scirpus is a genus of grass-like species in the sedge family Cyperaceae many with the common names club-rush, wood club-rush or bulrush (see also bulrush for other plant genera so-named). They mostly inhabit wetlands and damp locations.

Taxonomy
The taxonomy of the genus is complex, and under review by botanists. Recent studies by taxonomists of the Cyperaceae have resulted in the creation of several new genera, including the genera Schoenoplectus and Bolboschoenus; others (including Blysmus, Isolepis, Nomochloa, and Scirpoides) have also been used. At one point this genus held almost 300 species, but many of the species once assigned to it have now been reassigned, and it now holds an estimated 120 species.

Description
Scirpus are rhizomatous perennial herbs, with 3-angled stems and flat grass-like leaves. The flowers are in clusters of small spikelets, often brown or greenish brown.  Some species (e.g. S. lacustris) can reach a height of 3 m, while S. sylvaticus is about 1.2 m and others, such as S. supinus, are much smaller, only reaching 20–30 cm tall.

Distribution
The genus has a nearly cosmopolitan distribution, found on every continent except Africa and Antarctica.

Ecology
Many species are common in wetlands and can produce dense stands of vegetation, along rivers, in coastal deltas and in ponds and potholes. Although flooding is the most important factor affecting its distribution, drought, ice scour, grazing, fire and salinity also affect its abundance. It can survive unfavourable conditions like prolonged flooding, or drought, as buried seeds

Scirpus species are used as food plants by the larvae of some Lepidoptera species, including Chedra microstigma and Scirpophaga nivella.
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