Senecio triangularis Hook.
arrow-leaved groundsel (arrowleaf ragwort; arrow-leaved ragwort)
Asteraceae (Aster family)

Introduction to Vascular Plants


© Jim Riley     (Photo ID #28872)


E-Flora BC Static Map

Distribution of Senecio triangularis
Click here to view the full interactive map and legend

Species Information

Perennial herb from a fibrous-rooted, woody stem-base or rhizome; stems erect, solitary or few, branched above, glabrous to sparsely short-hairy above, 0.2-1.5 m tall.
Basal leaves triangular to heart-shaped, squared-off at the base; strongly toothed, stalked, 2.5-10 cm long including the stalks, 0.4-4.5 cm wide, hairless except for short hairs on the veins beneath, sometimes deciduous by flowering time; stem leaves similar, larger, 2.5-25 cm long, 0.4-8.5 cm wide, gradually reduced upwards, becoming unstalked.
Heads with ray and disk flowers, few to more often numerous on sparsely hairy stalks in a short, flat-topped inflorescence; involucres 7-12 mm tall; involucral bracts lanceolate, conspicuously black-tipped, sometimes also sparsely hairy or rarely with inconspicuous unstalked glands at the tips; bracteoles conspicuous, black-tipped, hairy; ray fowers yellow, mostly 7-14 mm long; disk flowers yellow.
Achenes oblong, faintly ribbed, glabrous; pappus of white hairlike bristles.

SourceThe Illustrated Flora of British Columbia


If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

USDA Species Characteristics

Flower Colour:
Blooming Period:
Mid Summer
Fruit/Seed characteristics:
Colour: Brown
Present over the Fall
Source:  The USDA


Ecological Framework for Senecio triangularis

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)
1568 3 2640
Slope Gradient (%)
16 0 420

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

160 0 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
5 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(72), BAFA(108), BWBS(15), CMA(6), CWH(31), ESSF(2363), ICH(201), IDF(18), IMA(35), MH(69), MS(202), SBPS(2), SBS(237), SWB(88)

Habitat and Range

Moist to mesic meadows, streambanks, avalanche tracks and forest openings from the lowland to lower alpine zones; common throughout BC; N to S AK, S YT and SW NT, E to SK and S to NM and CA.

SourceThe Illustrated Flora of British Columbia


Synonyms and Alternate Names:
Senecio gibbsonsii Greene
Senecio triangularis var. angustifolius G.N. Jones