Difference between revisions of "Machaeranthera tanacetifolia"

Revision as of 18:45, 24 September 2019

Copyright: Flora of North America Association

Annuals or biennials, 5–100 cm. Leaves 8–110 × 4–40 mm. Involucres hemispheric, 6–11 mm. Phyllaries (24–)40–80(–100) in 3–6 series, linear-lanceolate to linear, 4–11 × 0.5–1.2 mm, apices usually spreading to reflexed, sometimes appressed, long-acuminate. Receptacles flat to convex, 3.5–8(–10) mm diam. Ray florets 12–40(–50); laminae 8–20 × 1–3.5 mm. Disc florets (18–)40–160; corollas 4–7 mm, glabrous or glabrate; lobes 0.3–0.7(–1) mm, glabrous. Cypselae 2–3.5(–4) mm; pappi 2–8 mm. 2n = 8.

Phenology: Flowering Mar–Oct.
Habitat: Grasslands, Larrea-dominated desert scrub, pine-oak and pinyon-juniper woodlands, streambeds, roadsides, disturbed areas
Elevation: 800–2500 m

Alta., Ariz., Calif., Colo., Kans., Mont., Nebr., Nev., N.Mex., Okla., S.Dak., Tex., Utah, Wyo., Mexico (Aguascalientes, Chihuahua, Coahuila, Durango, Nuevo León, San Luis Potosí, Zacatecas).

Discussion

Machaeranthera tanacetifolia is present in the southern Rocky Mountains, western Great Plains, and southwestern desert regions. It has also been reported from Illinois and New York, but in both cases is most likely introduced. Because of its large showy heads, M. tanacetifolia is sometimes planted as an ornamental.

Selected References

None.

Lower Taxa