Genus:
Poa L.

Poa chambersii Soreng

This species is accepted, and its native range is Oregon.

[GB]
Morphology General Habit
Perennial; caespitose. Rhizomes short. Butt sheaths persistent and investing base of culm. Culms geniculately ascending; 10-50 cm long; 0-2 -noded. Lateral branches ample. Leaf-sheaths tubular for much of their length; with 0.4-0.9 of their length closed; keeled. Ligule an eciliate membrane; 0.5-2 mm long; glabrous on abaxial surface; erose; truncate, or obtuse. Leaf-blades flat, or conduplicate; 4-8 cm long; 2-5 mm wide. Leaf-blade surface smooth; glabrous.
Morphology Reproductive morphology Inflorescences
Gynodioecious (male, in this context, indicating the bisexual state), or dioecious. Inflorescence a panicle. Panicle contracted; oblong, or ovate; 2-9 cm long; bearing few spikelets. Primary panicle branches ascending; 1-2 -nate; 1-3.5 cm long. Spikelets solitary. Fertile spikelets pedicelled.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 2-7 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 6-12 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes smooth, or scaberulous. Floret callus glabrous, or woolly (slightly). Male spikelets resembling female.
Fertile
Spikelets comprising 2-7 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 6-12 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes smooth, or scaberulous. Floret callus glabrous, or woolly (slightly).
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 3.5-4.5 mm long; 1 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume elliptic; 3.5-4.5 mm long; 0.6-0.8 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.
Morphology Reproductive morphology Flowers Florets
Fertile lemma ovate; 5-7 mm long; membranous; keeled; 5-7 -veined. Lemma midvein eciliate, or ciliolate; hairy below. Lemma margins eciliate, or ciliolate; hairy below. Lemma apex acute. Palea 1 length of lemma. Palea keels scabrous. Apical sterile florets resembling fertile though underdeveloped.
Morphology Reproductive morphology Flowers
Lodicules 2; 0.6 mm long; membranous. Anthers 3; 1.8-3.7 mm long.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp; 2 mm long. Hilum punctiform.
sex Male
Male spikelets resembling female.
Distribution
North America: northwest USA.
Reference
Poeae. Soreng 1999.

Native to:

Oregon

Poa chambersii Soreng appears in other Kew resources:

First published in Novon 8: 195 (1998)

Accepted by

  • Clayton, W.D., Harman, K.T. & Williamson, H. (2006). World Grass Species - Synonymy database The Board of Trustees of the Royal Botanic Gardens, Kew.
  • Flora of North America Editorial Committee (2007). Flora of North America North of Mexico 24: 1-908. Oxford University Press, New York, Oxford.

Literature

Kew Backbone Distributions

  • Flora of North America Editorial Committee (2007). Flora of North America North of Mexico 24: 1-908. Oxford University Press, New York, Oxford.

  • GrassBase - The Online World Grass Flora

    http://creativecommons.org/licenses/by-nc-sa/3.0

  • Kew Backbone Distributions

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0