Fig. 10 FIVE FINGER FERN (Adiantuin pedatum). This fern lives on moist, rocky walls, receiving only a few hours of sunlight each day, or no direct sunlight.

ADIANTUM

A distinctive group containing our most graceful and delicate ferns. The slender leaf stalk is black or brown, often shiny. The extensive underground stems, called rhizomes, may form mats. Sori marginal, the sporangia attached to the reflexed lobes of the segments. Veins of the leaflets, easily visible, divided into two equal divisions each time, never joining or forming a net-like pattern.

These ferns grow in moist places, usually protected from direct sunlight during part or most of the day, often where they have a north exposure.

Adiantum is used with flowers for corsages, especially when the leaf stalk has been singed in an open flame to prevent wilting. They are commonly cultivated in hanging boxes, and planted in shady corners of gardens. Most native species from higher altitudes die down during the winter. The dark leafstalks were used for black designs in baskets by several tribes of Indians in California (Kroeber).

Fig. 11 Upper: FIVE FINGER FERN (Adiantum pedatum). Lower Right: Fertile pinna. Lower Left: COMMON MAIDEN HAIR (Adiantum capillus-veneris)

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Fig. 11 Upper: FIVE FINGER FERN (Adiantum pedatum). One frond with its finger-like branches. Pinnae are sterile. Lower right: Fertile pinna of the same species. Lower left: COMMON MAIDEN HAIR (Adiantum capillus-veneris). Some pinnae are sterile, others have moon-shaped marginal sort. Pinnate branches along the entire leaf stalk distinguish this fern from the Five Finger Fern.

KEY TO THE SPECIES:

Leaf stalk forked only at the top, each fork bearing 3-8 pinnae on upper side A. pedatum
Leaf stalk with branches all along its sides

Pinnae not deeply cut between sori, margin of fertile pinnules rounded A. jordanii
Pinnae more deeply incised between sori, margin of pinnules irregular A. capillus-reneris

FIVE FINGER FERN

Adiantum pedatum L. (Fig. 10, 11)

A. pedatum var. aleuticum

Distinguished by leaf stalk one or two feet high forked only near summit, each fork bearing a number of pinnae. Pinnules arranged pinnately, all their sori being on the upper edge. Upper edge incised or notched between sori, lower edge smooth.

Common in higher mountains of the Sierra Nevada from 3,000 to 10,000 feet elevation. It may be observed along several trails leading out of Yosemite Valley as on the horse trail to Nevada Falls, in Sequoia National Park along the middle fork of the Kaweah River. It is known from California to Alaska, in several eastern states, and in Canada from Newfoundland to Ontario.

CALIFORNIA MAIDEN HAIR

Adiantum jordanii C. Mull. ex Kuhn (Fig. 12)

A. emarginatum.

Erect fronds 1/2 to 2 feet high, distinctive because there are pinnate branches all along the leaf stalk. Pinnules nearly round or broadly fan-shaped with sori located at ends of veinlets. Very shallow incisions between two successive sori.

Found in central Sierra foothills from 2,000 to 3,000 feet elevation. It can be observed near the highway west of El Portal, in the vicinity of Copperopolis, La Grange, and Jacksonville, Tuolumne County, in the months of February or March to June. It is common in coastal areas from the northern part of lower California to southern Oregon, and has been reported from western New Mexico.

COMMON MAIDEN HAIR

Adiantum capillus-veneris L. (Fig. 11)

Branching similar to A. jordanii, but this species has more drooping fronds and pinnae are more wedge-shaped, sori shorter, distinctively moon-shaped, giving the fertile pinnules an irregular outline. Sterile pinnae deeply incised. Leaf form somewhat variable.

Grows on cool, shaded canyon walls at lower elevations, especially on lime soils. Although this species is widespread in its total distribution, it is not common in the Sierra. Known in California from the coastal and inland areas as well as in many scattered locations in the United States and in temperate and sub-tropical regions around the world.

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Fig. 12 CALIFORNIA MAIDEN HAIR (Adianlum jordanii). A fertile frond on the left side, a sterile one on the right. This fern closely resembles the Common Maiden Hair in its branching. Here the sori are net moon-shaped and notches between sori are never deeply cut.

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