Fragile Fern
Cystopteris fragilis (L.) Bernh. (C. dickieana R. Sim)
overview
Delicate, small fern to 30 cm tall. Rhizomes are light brown, short and densely scaly. Stipes are straw-coloured, hairless and shorter than the blades. Blades are lance-shaped, taper at both ends and are two to three times pinnate with 8-18 pairs of leaflets; lower leaflets reduced in size and ultimate segments irregularly toothed. The small, round sori are partially covered with a delicate, hood-like, somewhat toothed or lobed indusium which soon withers and curls back (Pojar and MacKinnon, 1994). Photo by Moralea Milne.
other names
brittle fern
family
Dryopteridaceae
ecological setting
Cool, moist to dry rocky forests and elevations. Often found on calcium-rich rock cliffs, crevices, ledges and talus slopes at all elevations (Pojar and MacKinnon, 1994). Very widely distributed across North America.
soil texture
Coarse-textured free-draining.
nutrients
Nitrogen medium, calcium rich.
soil reaction salinity
Slightly acidic to moderately calcarious (Bernh, 2002).
moisture regime
Dry to fresh.
shade tolerance
Shade tolerant. Prefers shady sites but will tolerate a limited amount of filtered sunlight (Bernh 2002)
landscaping
Attractive ornamental for the dry, shady rock garden.
seed collection time
When spores are well developed (tan or brown in colour) in the sori, tie a clear plastic bag over fronds and shake until spores are dislodged. Spread spores on the surface of a 1:1 peat/vermiculite planting mixture. Set container in the dark for a few days before moving to a well-lit location. Keep the planting medium damp by covering with glass or clear plastic. Spores will germinate in one to three months if kept at 20o C. Gametophytes will appear after one to three months. Keep the planting medium damp by covering with glass or clear plastic. As gametophytes grow, continually thin 0.5 cm plugs into larger individual containers with moist, well-draining soil-less medium leaving 2.5 cm between each plug. Cover to retain humidity and place in bright area but not in full sunlight. Mist gametophytes to encourage fertilization. Sporphytes will appear in one to six months and once fronds reach 2.5 cm in height they can be transferred to individual containers.
vegetative propagation
Can be propagated by division in the spring and by rhizome cuttings (Bernh, 2002).
additional info and photos
For more information and pictures, visit the E-Flora BC website at www.eflora.bc.ca.