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MOUNT RAINIER NATIONAL PARK NATURE NOTES
Vol. XV March - 1937 No. 1


Maidenhair Fern
1. Frond of the Maidenhair Fern (Adiantum pedatum, var. aleuticum) illustrating dichotomous branching habit (x1). 2. Pinnule (underside) illustrating dichotomous venetion, oblique triangular-oblong outline and cleft upper margin (x6). Note also the crescent shaped recurved portions of the margin, beneath which the sori are found.

MAIDENHAIR FERN.
(Adiantum pedatum L., var. aleuticum Rupr.)

Our variety of that well known, widely distributed and beautiful fern (A. pedatum) is quite common in Mt. Rainier National Park. Locally it is found from the lower park boundaries to about 3500', being very common in the talus near the West Side Highway on the east face of Mt. Wow just below Fish Creek. It is generally considered to be a plant that prefers a moist, cool habitat but in this park it is often found in dry, rocky soil as in the case just mentioned. The general appearance of the Maidenhair Fern is one of delicate beauty with its loose spreading fronds arranged in an open tuft. These fronds are from 10" to 40" long, 3 compound and generally oval or kidney-shaped in outline. The leafstalk is shiny, appearing as if varnished, and either dark chestnut brown or black. It is much longer than the foliate portion of the frond and divided at the apex into two branches or pinnae. The pinnules are numerous and lacking a midvein - venation being dichotomous. The upper margin of these pinnules is characterized by several deep clefts, is obliquely triangular-oblong in general outline and joined to the stem by a slender, short petiole. They are very thin and light green in color. The spores are borne in sori which may be found beneath the crescent-shaped, recurved portions of the leaf margin and the rhizome is thick, short, of a creeping habit and possesses numerous hair-like, wiry rootlets which, according to some botanists, accounts for the common name. The Maidenhair Fern is a herbaceous plant, reaching maturity about mid-July in this park.

Dr. T. C. Frye reports that the Indians of the Puget Sound region used the fronds of this fern in the drying of berries. A lattice of cedar strips was prepared over a fire upon which the fronds were laid to receive a layer of berries. After drying the pinnules of the fern were segregated from the fruit by winnowing.

-oOo-

LACE FERN or HAIRY LIP-FERN
(Cheilanthes gracilliama D.C. Eaton)

This fern is one of the smaller and more inconspicuous of our native ferns, yet it may be frequently encountered by those who venture about the rocky, more inaccessible places. It prefers a habitat among the rocks or on dry cliffs in the Hudsonian and lower Arctic-alpine zones. The soil where it grows is generally thin and very poor. Its botanical range includes British Columbia and the states of Montana, Idaho, Washington, Oregon, California and Nevada. Locally it is found from 5000' to 7000' in suitable situations. The fronds are from 4"-12" long and densely clustered in a compact tuft. These fronds, individually, are linear to oblong in outline, two compound (though very occasionally they may be 3-compound) deep green above and brownish, densely fuzzy on the underside. Pinnules are densely crowded which impart to the plant a "lacy" appearance, probably accounting for one of its common names. The spores are borne beneath the recurved margins of these pinnules. The stems of the fronds are very slender, shiny and chestnut brown in color and are nearly as long as the foliate portion of the leaf.

Altogether this plant makes a very pleasing appearance in its rocky, inhospitable habitat, and it is said that it is a very fine plant for a rock garden. It is common on Pinnacle Peak and has been noted at other points throughout the park in similar locations.

-oOo-

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17-Jun-2002