Streptopus amplexifolius (L.) DC.
clasping twistedstalk (claspleaf twistedstalk)

Introduction to Vascular Plants


© Bryan Kelly-McArthur     (Photo ID #79151)


E-Flora BC Static Map

Distribution of Streptopus amplexifolius
Click here to view the full interactive map and legend

Species Information

Perennial herb from a thick, short rhizome covered with fibrous roots; stems erect, 40-120 cm tall, branched, sometimes bent at nodes (zigzag), smooth throughout or coarse-hairy on the lower third.
Stem leaves several, egg-shaped to broadly lanceolate, 5-15 cm long, 2-6 cm wide, unstalked, tapering to a clasping base, glaucous beneath, the margins entire or minutely toothed; basal leaves lacking.
Inflorescence of 1 or sometimes 2, stalked flowers drooping from leaf axils, the stalks 2-5 cm long, jointed and abruptly bent or kinked, smooth; flowers greenish-white to yellowish-green, bell-shaped, of 6 similar, distinct tepals, the tepals 8-14 mm long, oblong-lanceolate, concavely tapering to long, pointed, spreading or bent-back tips; stamens 6; pistil 1, 3-chambered.
Berries, egg-shaped to cylindric-ellipsoid, yellow to red, often becoming dark purple, 10-18 mm long; seeds several to many.
Two varieties occur in BC:

1. Stems coarsely hairy below the first branches; leaves with tiny, irregularly spaced teeth; plants mostly from west of the Coast-Cascade Mountains................... var. amplexifolius

1. Stems smooth; leaf margins entire; plants mostly from east of the Coast-Cascade Mountains................... var. chalazatus Fassett

SourceThe Illustrated Flora of British Columbia


Ecological Framework for Streptopus amplexifolius

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres)
964 0 2097
Slope Gradient (%)
19 0 410

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

0 0 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
4 0 8
Modal Nutrient Regime
# of field plots
 species was recorded in:
Modal BEC Zone Class

All BEC Zones (# of stations/zone) species was recorded in

AT(5), BAFA(2), BWBS(97), CDF(54), CWH(1504), ESSF(1855), ICH(1608), IDF(144), IMA(2), MH(137), MS(384), PP(8), SBPS(20), SBS(1190), SWB(4)

Habitat and Range

Moist forests, streambanks, thickets, avalanche tracks and clearings in the lowland and steppe to subalpine zones; common throughout BC; var. amplexifolius - circumboreal, N to AK, YT and NT, E to NF and S to NC, TN, MN, SD, NM, AZ and CA; Greenland, Eurasia; var. chalazatus - amphiberingian, N to AK, E to AB and S to SD, NM, UT, ID and OR; E Asia.

SourceThe Illustrated Flora of British Columbia