Poaceae
Calamagrostis

Calamagrostis breweri Thurb.

First published in S.Watson & al., Bot. California 2: 280 (1880)
This species is accepted
The native range of this species is Oregon to N. Central California. It is a perennial and grows primarily in the temperate biome.

Descriptions

Morphology General Habit
Perennial; caespitose. Culms 15-30 cm long. Lateral branches lacking. Leaves mostly basal. Ligule an eciliate membrane; 0.5-1.5 mm long; obtuse. Leaf-blades filiform; conduplicate, or involute; 0.5-1 mm wide.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle. Panicle open; ovate; 3-8 cm long. Primary panicle branches spreading; 1-2 cm long. Spikelets solitary. Fertile spikelets pedicelled.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 3.3-4 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent. Floret callus hairs 0.5 mm long; 0.15 length of lemma.
Fertile
Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 3.3-4 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent. Floret callus hairs 0.5 mm long; 0.15 length of lemma.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; similar; reaching apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of upper glume; membranous; purple; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface asperulous. Lower glume apex acuminate. Upper glume lanceolate; 3.3-4 mm long; 1 length of adjacent fertile lemma; membranous; purple; 1-keeled; 1-3 -veined. Upper glume apex acuminate.
Morphology Reproductive morphology Flowers Florets
Fertile lemma lanceolate; 3-4 mm long; membranous; without keel; 5 -veined. Lemma apex dentate; 4 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.1-0.2 way up back of lemma; geniculate; 5-6 mm long overall; with twisted column. Palea 1 length of lemma. Rhachilla extension 0.33 length of fertile floret; pilose.
Morphology Reproductive morphology Flowers
Lodicules 2; 0.7 mm long. Anthers 3; 1.3 mm long. Stigmas 2.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp. Hilum punctiform. Disseminule comprising a floret.
Distribution
North America: southwest USA.
Reference
Aveneae. Fl Pac NW 1994.
[GB]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0

  • GrassBase - The Online World Grass Flora

    • Clayton, W.D., Vorontsova, M.S., Harman, K.T. and Williamson, H. (2006 onwards). 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 Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0