Ranunculus orthorhynchus Hook.
straight-beaked buttercup (straightbeak buttercup)
Ranunculaceae (Buttercup family)

Introduction to Vascular Plants

Photograph

© Jamie Fenneman     (Photo ID #9159)


Map

E-Flora BC Static Map

Distribution of Ranunculus orthorhynchus
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Species Information

General:
Perennial herb from mass of thick, fibrous roots, sometimes fleshy and more or less tuberous; stems usually several, decumbent to erect, 20-60 (100) cm tall/long, somewhat hollow; plants stiff-hairy to less commonly smooth.
Leaves:
Basal narrowly egg-shaped to oblong or semicircular, the blades usually pinnately 3- to 5-lobed or -parted, 3-12.5 cm long, 2.5-14 cm wide, the segments or leaflets undivided or 1- to 2-times lobed or parted, the ultimate segments linear to circular, margins toothed or entire, tips rounded to narrowly pointed, the stout stalks to 25 cm long; stem leaves alternate, shorter-stalked, more deeply divided, the ultimate segments linear.
Flowers:
Inflorescence a few-flowered terminal cyme; flower stalks to 15 cm long; receptacle stiff-hairy; petals 5 or 6, distinct, yellow or red on the back, yellow above, 8-18 mm long, 4-11 mm wide, nectary on upper surface, the nectary scale smooth, 0.5-1 mm long; sepals 5, bent back 1-2 mm from base, early deciduous, often purplish-tinged, 5-11 mm long, 2-4 mm wide, stiff-hairy, soft-hairy or smooth; stamens 50-70; pistils 5-50.
Fruits:
Achenes, several to many in a globe- to egg-shaped head 5-13 mm long, 6-10 mm wide, the achenes broadly egg-shaped, 2.8-4.5 mm long, 1.8-3.2 mm wide, smooth, margins conspicuous and slightly keeled above; beaks persistent, narrowly lanceolate- to awl-shaped, straight, 1.8-4 (5) mm long.
Notes:
Two varieties are recognized in BC:

1. Petals yellow, tinged with red or purple on the back, usually over twice as long as wide; heads of achenes hemispheric or sometimes globe-shaped, 5-7 mm long................ var. orthorhynchus

1. Petals yellow, not tinged with red or purple, usually less than twice as long as wide; heads of achenes globe- or egg-shaped, 8-13 mm long..................... var. platyphyllus A. Gray

SourceThe Illustrated Flora of British Columbia

Ecology

Ecological Framework for Ranunculus orthorhynchus

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

Avg

Min

Max

Elevation (metres)
0 0 3
Slope Gradient (%)
0 0 2

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

0
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
6 5 7
Modal Nutrient Regime
Class
D
# of field plots
 species was recorded in:
17
Modal BEC Zone Class
CWH

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

CWH(17)

Habitat and Range

Wet to moist meadows, thickets, streambanks, and tidal marshes in the lowland, steppe and montane zones; var. orthorhynchus - common in coastal BC, rare inland, var. platyphyllus - rare along the coast, more frequent inland in S BC; N to SE AK and S to WY, UT, NV and CA.

SourceThe Illustrated Flora of British Columbia