Artemisia tridentata
Artemisia arbuscula
big sagebrush, blue sagebrush, common sagebrush, mountain sagebrush, sagebrush
black sagebrush, dwarf sagebrush, little sagebrush, low sagebrush
gray-brown, glabrate (bark gray, exfoliating in strips).
gray-green to brown, glabrate (diffusely branched from bases, brittle).
persistent, gray-green;
blades usually cuneate, (0.4–)0.5–3.5 × 0.1–0.7 cm, 3-lobed (lobes to 1/3 blade lengths, 1.5+ mm wide, rounded), faces densely hairy.
(vegetative stems) persistent, gray-green;
blades broadly to narrowly cuneate, 3–10 × 2–5 mm, lobed (lobes 3, oblong-linear, to 1/3 blade lengths, mostly 1–3 mm wide, flat, obtuse, laterals sometimes 2–3-fid; leaves on flowering stems deciduous, blades narrowly cuneate, deeply 3-lobed), faces densely hairy (not sticky resinous).
lanceolate, (1–)1.5–4 × 1–3 mm.
campanulate or globose-ovoid, (1.5–)2–4(–5) × 1.5–4.5 mm.
3–8;
corollas 1.5–2.5 mm, glabrous.
4–6(–10);
corollas 1.5–2 mm, glabrous.
oblanceolate to widely obovate, densely tomentose.
(margins green) ovate (outer) to oblong, pubescent or tomentose.
(usually erect, on slender peduncles) in paniculiform arrays 5–30 × 1–6 cm.
usually borne singly, rarely (1–4, erect, mostly sessile, in pedunculate clusters) in spiciform or paniculiform arrays 2–9 × 0.5–2 cm (branches slender).
1–2 mm, hairy or glabrous, glandular.
(light brown) 0.7–0.8 mm, resinous.
Artemisia tridentata
Artemisia arbuscula
Subspecies 4 (4 in the flora).
Artemisia tridentata has undergone considerable taxonomic revision in the past century and circumscription of subspecies remains a topic of considerable controversy. Workers in the field should be aware of the morphologic variation within the subspecies across the range of the species (i.e., approximately from the Sierra Nevada in the west to the plains of the Rocky Mountains in the east). Because rangeland managers and conservationists can often identify local morphologic and chemical races based on grazing or habitat preferences of wildlife and domestic animals, some impetus exists to further subdivide the subspecies within A. tridentata at the varietal level. This treatment of the species complex remains conservative in light of the need for further study. As to chemical differences among the subspecies, aroma is often used to distinguish subspecies in the field. Volatile resins in the plants are strongly aromatic and, when crushed, leaves have very distinctive (although not easily described) aromas.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Subspecies 3 (3 in the flora).
Artemisia arbuscula is one of the more perplexing species in the Tridentatae complex. Anatomic and morphologic characteristics suggest multiple hybrid origins for the subspecies. Deciduous leaves of flowering stems in plants that otherwise have persistent leaves suggest a hybrid origin involving plants of the A. tridentata and A. cana lineages. In most instances, populations of A. arbuscula appear to be reproductively stable. The disposition of Artemisia arbuscula subsp. longicaulis Winward & McArthur (with 2n = 54) has not been determined.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Shrubs 100–200(–300) cm (leaf blades: lengths usually 3+ times widths); heads in relatively broad, paniculiform arrays | → 2 |
1. Shrubs 30–150 cm (leaf blades: lengths usually less than 3 times widths); heads in relatively narrow, paniculiform arrays | → 3 |
2. Involucres 1.5–2.5 × 1–2 mm; deep, well drained (usually sandy) soils in valley bottoms, lower montane slopes along drainages | subsp. tridentata |
2. Involucres 2–4 × 1–2 mm; loose, sandy soils of valleys and foothills | subsp. parishii |
3. Shrubs, 60–80(–150) cm (crowns flat-topped); heads in arrays 10–15 cm; involucres 2–3 × 1.5–3 mm; mountains | subsp. vaseyana |
3. Shrubs, 30–50(–150) cm (crowns rounded); heads in arrays 2–6(–8) cm; involucres (1–)1.5–2 × 1.5–2 mm; usually cold-desert basins and high plateaus, sometimes foothills | subsp. wyomingensis |
1. Involucres 2–4.5 mm diam.; usually in rocky soils; flowering mid–late summer | subsp. arbuscula |
1. Involucres 1.5–2.5 mm diam.; clays or stony soils; flowering early spring–late summer | → 2 |
2. Leaves broadly cuneate (4–10 × 2–5 mm, often irregularly lobed, lobes rounded, middle lobes overlapping lateral lobes); usually in clay soils; flower- ing early spring | subsp. longiloba |
2. Leaves narrowly cuneate (5–10 × 3–6 mm, lobed, lobes 1/2+ blade lengths, laterals to 1 mm wide, of-ten acute); usually in stony soils; flowering mid–late summer | subsp. thermopola |
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
PNW Herbaria, Turner Photog. 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
- Local floras: CA, OR, WA
- Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria
- WildflowerSearch
- iNaturalist (observations)
- USDA Plants Database
- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
