rattlesnake fern (Botrychium virginianum)
Botrychium virginianum (L.) Sw. ssp. europaeum (Angstr.) Jáv.
Botrychium virginianum (L.) Sw. var. europaeum Angstr.
Botrypus virginianus (L.) Michx.
TAXONOMY: The currently accepted scientific name of rattlesnake
fern is Botrychium virginianum (L.) Sw.
NATIVE STATUS: Native, United States and Canada.
GENERAL BOTANICAL CHARACTERISTICS: Rattlesnake fern is a deciduous fern consisting of a single sterile leaf about 4-8" long and 5-
10" across on an erect basal stalk about 2-6" tall; this leaf is sessile. On
some ferns, a second fertile leaf is produced on a long stalk that originates
from the base of the sterile leaf. The basal stalk is light green to dark red,
glabrous, terete, rather succulent, and stout. The sterile leaf is ascending
or horizontal to the ground. It is light to medium green, deltate in outline,
bipinnate-pinnatifid, and glabrous. The sterile leaf is pinnately divided in-
to 5-12 pairs of leaflets that are individually deltate-ovate to lanceolate-
oblong in outline; each leaflet is pinnately divided with up to 12 pairs of subleaflets that are individually oblong-lanceolate to lanceolate in outline.
Each subleaflet is pinnatifid and coarsely dentate along its margins, divid-
ing shallowly to deeply into several pairs of lateral lobes that are irregular-
ly shaped. The stalk of the fertile leaf is 3-6" long, light green, terete,
slightly succulent, and glabrous. At its apex, there is a glabrous fertile leaf
about 3-6" long and about one-half as much across; its structure is bipin-
nate to pinnate. The leaflets and subleaflets are stalk-like in shape with
sessile sporangia (spore-boring structures) along their sides; they are in-
itially light green, but become brown at maturity. Individual sporangia are
globoid in shape and 1 mm. across or less; they are initially light green,
but become yellow and finally brown when their spores are released. A
fertile leaf begins to develop before the sterile leaf has fully unfolded dur-
ing the late spring. Spores are released from the fertile leaf during the sum-
mer. They are distributed by the wind. The root system is fibrous and fleshy. Occasionally, clonal offsets are produced.
REGENERATION PROCESS: Rattlesnake fern has short rootstocks and
usually fleshy roots.
HABITAT TYPES: Habitats include rich mesic to dry-mesic woodlands,
wooded slopesand ravines, upland savannas, open disturbed woodlands,
and areas along paths in wooded areas. This fern is also found in moist
woodlands in areas that are well-drained. It is often found in woodlands
that are dominated by oaks (Quercus spp.) and hickories (Carya spp.),
sometimes colonizing areas with a history of disturbance.
SITE CHARACTERISTICS: Rattlesnake fern prefers partial sun to light
shade, mesic to dry-mesic conditions, and a fertile loamy soil with an abun-
dance of decaying organic matter.
SEASONAL DEVELOPMENT: Spores are produced in September
GENERAL DISTRIBUTION: Rattlesnake fern is found throughout
the United States and Canada, absent only in the far northern territories
SKY MEADOWS DISTRIBUTION:
Fern specimens can be found on trails marked in red.
Appalachian Trail/Old Trail
South Ridge/North Ridge
Rolling Meadows/ Lost Mountain
The specific distribution of rattlesnake fern has not been determined.
IMPORTANCE AND USES: Very little is known about floral-faunal relationships for rattlesnake fern. Sometimes evergreen ferns in this genus
are browsed by the ruffed grouse, wild turkey, and white-tailed deer, but
this usually happens during the winter when little else is available. How-
ever, in contrast to other species of its genus in North America, rattlesnake
fern is deciduous, rather than evergreen.
Rattlesnake fern is difficult to grow from spores or rootstocks; therefore, it
is not a significant ornamental plant.
Calendar of Events
Sky Meadows Park
Crooked Run Valley