Poa arida |
Poa piperi |
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Piper's bluegrass |
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Habit | Plants perennial, dioecious, 20–55 cm; loosely cespitose, rhizomatous. | |
Culms | nodes terete, 0–1 exserted. |
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Basal branching | extra- and intravaginal. |
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Leaves | sheaths closed 33–50% of their length, bases of basal sheaths glabrous, collars of at least some leaves usually sparsely short-hairy; ligules 1–2 mm, blades of tillers to 40 cm long; upper surface moderately to densely scabrous or minutely hairy on and between the veins; cauline blades involute, 1–3 mm wide; lower surfaces smooth; upper surfaces sometimes sparsely hairy; blades much reduced higher on the culm; uppermost blades 1–4.5 cm. |
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Inflorescences | erect to nodding, lanceoloid to ovoid, loosely contracted; sparse, 4–8 cm; spikelets 18–60; branches ascending; lax, 3–8 cm long, 1–2 per node, with 3–8 spikelets. |
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Spikelets | 6–9(11)mm; to 3 times as long as wide; florets 2–5(7); rachilla internodes 1–2 mm long. |
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Glumes | subequal; lower glumes 3-veined. |
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Calluses | with diffuse; soft cobwebby hairs about 50% as long as the lemma. |
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Lemmas | lanceolate, 4–6(7)mm, distinctly keeled, glabrous throughout; smooth or sparsely to moderately finely scabrous; keels scabrous; tips acute. |
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Anthers | vestigial and 0.1–0.2 mm, or 2–3 mm. |
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2n | =28. |
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Poa arida |
Poa piperi |
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Distribution | ||
Discussion | Forest openings on serpentine soils. 300–1600m. CR, Sisk. CA. Native. Poa piperi is a dioecious, usually glaucous grass with nearly transparent glumes and cobwebby callus hairs. |
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Source | Flora of Oregon, volume 1, page 462 Rob Soreng, Barbara Wilson, Richard Brainerd, Nick Otting |
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Sibling taxa | ||
Web links |