Achnatherum stillmanii (Bol.) Barkworth:
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Stipa stillmanii Bol.:
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Global Range: Achnatherum stillmanii is restricted to the northern High Sierra Nevada in California.

Perennials, Terrestrial, not a quatic, Rhizomes present, Rhizome short and compact, stems close, Stems nodes swollen or brittle, Stems erect or ascending, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems with inflorescence 1-2 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly basal, below middle of stem, Leaves mostly cauline, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence a contracted panicle, narrowly paniculate, branches appressed or ascending, Inflorescence a dense slender spike-like panicle or raceme, branches contracted, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Flowers bisexual, Spikelets pedicellate, Spikelets dorsally compressed or terete, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating above the glumes, glumes persistent, Spikelets disarticulating beneath or between the florets, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes equal to or longer than adjacent lemma, Glumes 1 nerved, Glumes 3 nerved, Glumes 4-7 nerved, Lemma coriaceous, firmer or thicker in texture than the glumes, Lemma 5-7 nerved, Lemma body or surface hairy, Lemma apex dentate, 2-fid, Lemma distinctly awned, more than 2-3 mm, Lemma with 1 awn, Lemma awn 2-4 cm long or longer, Lemma awn fro m sinus of bifid apex, Lemma awn twisted, spirally coiled at base, like a corkscrew, Lemma awn twice geniculate, bent twice, Lemma margins inrolled, tightly covering palea and caryopsis, Lemma straight, Callus or base of lemma evidently hairy, Callus hairs shorter than lemma, Palea present, well developed, Palea membranous, hyaline, Palea about equal to lemma, Palea longer than lemma, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear.

Isotype for Stipa stillmanii Bol.
Catalog Number: US 556922
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Verification Degree: Card file verified by examination of alleged type specimen
Preparation: Pressed specimen
Collector(s): H. Bolander
Year Collected: 1870
Locality: Blue Canon, Sierra Nevada Mts., California, United States, North America

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: 21 - 80

Comments: The number of distinct occurrences is unknown but there are 68 accession records in the Consortium of California Herbaria database as of August 2007. Forty-five of these are recent collections since 1970.

United States

Rounded National Status Rank: N3 - Vulnerable

Rounded Global Status Rank: G3 - Vulnerable

Reasons: Achnatherum stillmanii is endemic to California. It grows in scattered locations in the high Sierra Nevada and according to the Flora of North America (2007), may be edaphically restricted.

Comments: Treated in the genus Achnatherum by Kartesz (1999); often (e.g., Kartesz 1994) treated in the genus Stipa.