E-Flora BC: Electronic Atlas of the Flora of British Columbia

Botrychium virginianum (L.) Sw.
rattlesnake fern
Ophioglossaceae (Adder's-tongue family)

Introduction to Vascular Plants

© Adolf Ceska  Email the photographer   (Photo ID #11449)

E-Flora BC Static Map
Distribution of Botrychium virginianum
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Species Information

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Deciduous perennial, (5) 10-40 cm tall.
2-pinnate, 0.5-1.5 times length of trophophores.
Triangular, unstalked, deciduous, thin, herbaceous, divided in 3's or 3- to 4-pinnate, up to 25-35 cm long and about as wide; pinnae to 12 pairs, approximate to overlapping; pinnules lanceolate with saw-toothed margins and pointed tips.

Source: The Illustrated Flora of British Columbia

USDA Species Characteristics

Blooming Period:
Late Spring
Source:  The USDA

Habitat / Range

Mesic to wet alluvial forests and swamps and river banks in the lowland, steppe and montane zones; frequent throughout BC; circumpolar, N to AK, YT and NT, E to NF and S throughout all of the U.S.; Eurasia.

Source: The Illustrated Flora of British Columbia


Ecological Framework for Botrychium virginianum

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) 18 861 1890
Slope Gradient (%) 0 10 205
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
1 195 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
2 5 8
Modal Nutrient Regime
Number of field plots
 species was recorded in:
Modal BEC Zone Class
All BEC Zones (# of stations/zone) species was recorded in: BWBS(6), CWH(20), ESSF(10), ICH(131), IDF(10), MS(14), PP(1), SBPS(6), SBS(51)


The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is montane boreal & cool temperate.

Synonyms and Alternate Names

Botrychium virginianum subsp. europaeum (Angstr.) Jáv.
Botrychium virginianum subsp. virginianum
Botrychium virginianum var. europaeum Angstr.
Botrypus virginianus

Taxonomic and Nomenclatural Links

Additional Photo Sources

General References