Poaceae
Agrostis

Agrostis densiflora Vasey

First published in Contr. U.S. Natl. Herb. 3: 72 (1892)
This species is accepted
The native range of this species is Oregon to California. It is a perennial and grows primarily in the temperate biome.

Descriptions

Morphology General Habit
Perennial; caespitose. Culms geniculately ascending; 15-60 cm long. Lateral branches lacking. Leaf-sheaths smooth, or scaberulous. Ligule an eciliate membrane; 3-4 mm long; pubescent on abaxial surface; truncate. Leaf-blades 5-10 cm long; 3-5 mm wide. Leaf-blade surface ribbed; scabrous.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle. Panicle spiciform; linear; continuous, or interrupted; 2-8 cm long; 0.5-1 cm wide. Spikelets solitary. Fertile spikelets pedicelled.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; 3 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus glabrous.
Fertile
Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; 3 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus glabrous.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; shiny. Lower glume lanceolate; 3 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume surface scabrous. Lower glume apex acute, or acuminate. Upper glume lanceolate; 3 mm long; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume surface scabrous. Upper glume apex acute, or acuminate.
Morphology Reproductive morphology Flowers Florets
Fertile lemma elliptic; 2.5 mm long; hyaline; without keel; 5 -veined. Lemma lateral veins extending close to apex. Lemma apex dentate; 4 -fid; muticous, or awned; 1 -awned. Principal lemma awn dorsal; arising 0.66-0.75 way up back of lemma; straight; 0-2 mm long overall. Palea 0.25-0.33 length of lemma; hyaline.
Morphology Reproductive morphology Flowers
Lodicules 2; membranous. Anthers 3; 0.75-1.5 mm long.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp. Hilum linear.
Distribution
North America: southwest USA.
Reference
Aveneae. Man US Gr 1994.
[GB]

Sources

  • 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 2023. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2022 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 2023. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2022 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0