Cyperus serotinus
Cyperus serotinus is a species of sedge that is native to parts of Europe and Asia.
The species was first formally described by the botanist Christen Friis Rottbøll in 1773.
Description
A moderately tall long-creeping sedge with solitary, triangular stem, leaves broad, minutely rough-toothed, diverging from the stem a little distance up, leaving a bare higher stretch of stem, the leaves as long as the stem or a little more. The 2-3 leafy bracts under the inflorescence resemble the leaves and much exceed the inflorescence.The inflorescence is clearly terminal and composed usually of a number of unequal radiating axes, themselves divided, with each ultimate axis unwinged, usually holding a fair number of flat spikelets that are well-separated, forming a loose or slightly congested ladder of stalked, projecting spikelets, with even the end spikelets separated from neighbouring ones.
The spikelets are 2–3.5 mm wide 10-15, each composed of 8-30 florets with broad scale-like glumes with wide pale margins and rounded tip, each floret maturing to hold a dark nut.
Similar Species
- C. longus - which has fewer, narrower spikelets per cluster, that are poorly separated, on broadly-winged axes, and the plant taller often with longer rays and lacks tubers.
- C. rotundus - which has conspicuous long-exerted stigmas, and as a plant is much smaller with slenderer stems to 40 cm, leaves to 30 cm x 5 mm, primary floral rays to 10 cm, the leaves seeming only at the base and shorter than the stem, uncommonly tubered, but with more 3-6) bracts and winged final floral axes, glumes longer and narrower, nut 3-sided. Large forms could superficially look like C. serotinus or C. longus.
- C. esculentus - smaller but with yellow to bright yellow inflorescence, arranged with a ladder effect as C. serotinus.