Poaceae
Calamagrostis

Calamagrostis porteri A.Gray

First published in Proc. Amer. Acad. Arts 6: 79 (1862)
This species is accepted
The native range of this species is N. Central & E. U.S.A. It is a perennial and grows primarily in the temperate biome.

Descriptions

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]

Morphology General Habit
Perennial. Rhizomes elongated. Culms erect; 60-120 cm long; 2-4 -noded. Leaf-sheaths smooth; glabrous on surface. Leaf-sheath oral hairs pubescent. Ligule an eciliate membrane; 2-4 mm long. Leaf-blades spreading; 4-8 mm wide. Leaf-blade surface scaberulous.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle. Panicle open; linear; equilateral, or nodding; 10-15 cm long. Primary panicle branches appressed, or ascending; 2-5 cm long. Panicle axis scabrous. Panicle branches scabrous. Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 4-6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 0.5 length of lemma.
Fertile
Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 4-6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 0.5 length of lemma.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface asperulous. Lower glume apex acute. Upper glume lanceolate; 4-6 mm long; 1.1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume surface asperulous. Upper glume apex acute.
Morphology Reproductive morphology Flowers Florets
Fertile lemma lanceolate; 3.5-5.5 mm long; membranous; without keel; 5 -veined. Lemma apex dentate; 4 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.2 way up back of lemma; geniculate; 3-5 mm long overall; not or scarcely exserted from spikelet; with a straight or slightly twisted column. Palea 1 length of lemma. Rhachilla extension pilose; with 3 mm long hairs.
Morphology Reproductive morphology Flowers
Lodicules 2. Anthers 3. Stigmas 2.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp. Hilum punctiform. Disseminule comprising a floret.
Distribution
North America: northeast USA and southeast .
Reference
Aveneae. N Amer Fl 1994.
[GB]

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

  • Herbarium Catalogue Specimens

    • Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2026. 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 2026. 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