Artemisia tripartita subsp. tripartita

Treatment appears in FNA Volume 19. Treatment on page 518.

Shrubs, 20–150 (–200) cm. Leaves 1.5–4 × 0.5–1.5 cm, lobes linear, to 0.5 mm wide. Heads in spiciform arrays (6–) 8–15 (–35) × (1–) 4–5 cm. Involucres 2–3 × 2 mm. Florets 4–8. Cypselae 1.8–2.3 mm. 2n = 18, 36.


Phenology: Flowering mid summer–late fall.
Habitat: Deep loam soils, usually igneous in origin
Elevation: 900–1900 m

Distribution

V19-882-distribution-map.gif

B.C., Idaho, Nev., Oreg., Wash., Wyo.

Discussion

Subspecies tripartita ranges throughout the Snake River and Columbia River basins, extending north through central British Columbia, where average annual precipitation is 375–800 mm. Because much of the range includes fertile agricultural land, much of the habitat has been lost to farming, and populations of subsp. tripartita occur as isolated islands along drainages and at the bases of mountain slopes. It may be one of the parents involved in the presumed hybrid origin of Artemisia arbuscula subsp. thermopola.

Selected References

None.

Lower Taxa

None.
not tailed +  and obtuse +
scarious +
spiciform +, racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Leila M. Shultz +
Rydberg +
decurrent +
Artemisia trifida +
compound +  and simple +
1.5 cm15 mm <br />0.015 m <br /> (4 cm40 mm <br />0.04 m <br />) +
3-lobed;cuneate +
0.5cm;2cm +
zygomorphic +, actinomorphic +  and (3-)5-merous +
red +  and pale-yellow +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
winged +  and monomorphic +
fertile +  and bisexual +
fertile +  and bisexual +
B.C. +, Idaho +, Nev. +, Oreg. +, Wash. +  and Wyo. +
900–1900 m +
gland-dotted +
hairy +  and glabrous +
pistillate +, staminate +  and neuter +
fertile +  and bisexual +
winged +  and beaked +
dispersed +
Deep loam soils, usually igneous in origin +
spiciform +  and paniculiform +
in subcapitate clusters +  and singly +
15 cm150 mm <br />0.15 m <br /> (35 cm350 mm <br />0.35 m <br />) +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
indeterminate +
8 cm80 mm <br />0.08 m <br /> (15 cm150 mm <br />0.15 m <br />) +
heterogamous +  and homogamous +
4 cm40 mm <br />0.04 m <br /> (5 cm50 mm <br />0.05 m <br />) +
each +  and sessile +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
turbinate;globose +
2 cm20 mm <br />0.02 m <br /> (?) +
sessile +  and petiolate +
gray-green +
deciduous +
1.5cm;4cm +
cauline +  and basal +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
deltate +
0mm +  and 0.5mm +
entire +  and dentate +
2-carpellate +
persistent +
Flowering mid summer–late fall. +
2 +  and 20 +
Mem. New York Bot. Gard. +
styliferous +, neuter +  and pistillate +
sterile +  and fertile +
conic;convex;conic;convex;flat +
2 +  and 5 +
exalbuminous +
Illustrated +  and Endemic +
1 +  and 10 +
not wand-like +
appendaged +  and truncate +
papillate +
Artemisia tridentata subsp. trifida +  and Seriphidium tripartitum +
Artemisia tripartita subsp. tripartita +
Artemisia tripartita +
subspecies +
funnel +  and subglobose +
cylindric +
perennial +, biennial +  and annual +