DELTA home

DELTA sample data

M. J. Dallwitz and L. Watson

Agrostis L.

Including Agraulus P. Beauv., Agrestis Bub., Anomalotis Steud., Bromidium Nees, Candollea Steud., Chaetotropis Kunth, Decandolea Batard, Didymochaeta Steud., Lachnagrostis Trin., Neoschischkinia Tsvelev, Notonema Raf., Pentatherum Nabelek, Podagrostis (Griseb.) Scribn., Senisetum Koidz., Trichodium Michaux, Vilfa Adans.

Habit, vegetative morphology. Annual, or perennial. Culms mostly (3–)5–100 cm high; herbaceous; unbranched above. Culm nodes glabrous. Leaf blades linear; 0.2–10 mm wide. Ligule an unfringed membrane.

Inflorescence. Plants bisexual, with bisexual spikelets. Inflorescence paniculate; open, or contracted (e.g., Bromidium); not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes persistent. Spikelets not secund.

Female-fertile spikelets, florets, fruit. Spikelets 0.8–4 mm long; compressed laterally; disarticulating above the glumes. Rachilla prolonged beyond the uppermost female-fertile floret, or terminated by a female-fertile floret. Hairy callus present (the hairs less than 0.5 mm long), or absent. Glumes two; more or less equal; long relative to the adjacent lemmas; awnless; carinate, or non-carinate. Upper glume 1 nerved. Spikelets with female-fertile florets only. Female-fertile florets 1. Lemmas entire to incised (usually truncate or emarginate, sometimes toothed via excurrent veins); awnless, or mucronate, or awned. Awns when present, 1, or 3 (Bromidium), or 5 (rarely); dorsal; geniculate; much shorter than the body of the lemma to about as long as the body of the lemma, or much longer than the body of the lemma (rarely). Lemmas non-carinate; without a germination flap; 3–5 nerved. Palea nearly always present; relatively long, or conspicuous but relatively short, or very reduced. Lodicules present; membranous; glabrous. Stamens 3. Ovary glabrous. Stigmas 2; white. Fruit small. Hilum short.

Photosynthetic pathway, leaf blade anatomy. C3; XyMS+. Midrib conspicuous, or not readily distinguishable; with one bundle only. Many of the smallest vascular bundles unaccompanied by sclerenchyma, or all the vascular bundles accompanied by sclerenchyma.

Taxonomy, distribution. Pooideae; Poodae; Aveneae. About 220 species. Holarctic, Paleotropical, Neotropical, Cape, Australian, and Antarctic.

Anatomical references. Metcalfe 1960; this project.

Illustrations. • Habit - Agrostis eriantha. Agrostis eriantha var. eriantha. • Floret.

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa. See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1998 onwards. DELTA sample data: descriptions, illustrations, identification, and information retrieval. Version: 19th October 2016.’.