Artemisia campestris
Sp. Pl. 2: 846. 1753.
Biennials or perennials, (10–)30–80(–150) cm, faintly aromatic; taprooted, caudices branched. Stems usually 1–5, turning reddish brown, (often ribbed) tomentose or glabrous. Leaves persistent or deciduous, mostly basal; basal blades 4–12 cm, cauline gradually reduced, 2–4 × 0.5–1.5 cm, 2–3-pinnately lobed, lobes linear to narrowly oblong, apices acute, faces densely to sparsely white-pubescent. Heads (pedunculate) in (mostly leafless) paniculiform arrays. Involucres broadly turbinate, 2.5–3(–5) × 2–3.5(–7) mm. Phyllaries (margins scarious) glabrous or villous-tomentose. Florets: pistillate 5–20; functionally staminate 12–30; corollas pale yellow, sparsely hairy or glabrous. Cypselae oblong-lanceoloid, somewhat compressed, 0.8–1 mm, faintly nerved, glabrous.
Distribution
Alta., B.C., Man., N.B., Nunavut, Ont., Que., Sask., Alaska, Ariz., Ark., Calif., Colo., Conn., Fla., Idaho, Ill., Ind., Iowa, Kans., Maine, Mass., Mich., Minn., Miss., Mo., Mont., N.C., N.Dak., N.H., N.J., N.Mex., N.Y., Nebr., Nev., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tex., Utah, Vt., Wash., Wis., Wyo., especially mountains and high latitudes, Eurasia.
Discussion
Subspecies ca. 7 (3 in the flora).
Artemisia campestris varies; each morphologic form grades into another. The present circumscription is conservative in that only three subspecies are recognized; the subspecies usually can be separated geographically as well as morphologically. Populations in western North America consist primarily of subsp. pacifica; east of the continental divide, plants are assigned to subsp. canadensis in northern latitudes and to subsp. caudata in southern latitudes.
Selected References
None.
Lower Taxa
Key
| 1 | Perennials; stems 2–5; basal rosettes persistent | Artemisia campestris subsp. pacifica |
| 1 | Biennials; stems 1(–3); basal rosettes not persistent (withering before flowering) | > 2 |
| 2 | Involucres globose, 3–4 × 3.5–5 mm; n of 50°, primarily Canada | Artemisia campestris subsp. canadensis |
| 2 | Involucres turbinate, 2–3 × 2–3 mm; s of 50°, e from Rocky Mountains to coastal North America | Artemisia campestris subsp. caudata |