Fimbristylis puberula |
Cyperaceae |
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sedge family |
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Habit | Herbs annual or perennial; cespitose or not, rhizomatous or not, rarely stoloniferous. | |
Culms | usually triangular, occasionally terete, rarely compressed or quadrangular; solid or pithy. |
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Leaves | basal and/or cauline, alternate, usually 3-ranked, bases forming cylindric sheaths enclosing stem; margins fused; ligules often present; blades frequently absent from some basal leaves, rarely from cauline leaves; when present flat, folded, rolled, or terete, linear. |
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Spikes | with a shortened axis; floral scales 1–many, crowded, spirally arranged, sometimes 2-ranked, usually each subtending a single flower or perigynium, sometimes proximal and/or distal scales empty; perigynia if present closed or open down one side, subtending and enclosing a very short rachilla-bearing 1-pistillate flower (Carex), sometimes also (0)3 staminate flowers and empty scales (Kobresia); spikes aggregated into secondary inflorescences that are panicles, often modified and sometimes consisting of a single spike; secondary inflorescences usually subtended by a foliaceous or scale-like or bristle-like bract. |
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Flowers | bisexual (unisexual in Carex and Kobresia); perianth absent or consisting of (1)3–6(30) bristles and/or scales; stamens usually (1)3, rarely more; ovary with 1–3(4) carpels, fused; locule 1; style undivided or branched; stigmas 2–3(4). |
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Fruits | achenes, usually trigonous or biconvex. |
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Fimbristylis puberula |
Cyperaceae |
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Distribution | ||
Discussion | Cosmopolitan. Approximately 100 genera; 16 genera treated in Flora. Cyperaceae (except Eleocharis) is characterized by unusual holocentric chromosomes, in which spindle fibers attach throughout the length of the chromosome, not at discrete centromeres. Also, reduction of chromosome number occurs at the second division of meiosis. These traits are shared with the related family Juncaceae but not by other vascular plants. Chromosome numbers in sedges are often very high, but it is unclear if this represents polyploidy or fragmentation of holocentric chromosomes. When collecting sedges, get the rhizomes (if present) because some species are distinguished by their cespitose or rhizomatous growth form. If possible, collect extra inflorescences because checking floral traits can be destructive. In some genera, species identification requires mature fruits. |
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Source | Flora of Oregon, volume 1, page 167 |
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Web links |
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