Hairy lipfern (Cheilanthes lanosa)* of the Brake Fern (Pteridaceae) family, formerly of the Polypody (Polypodiaceae) family, is a small to moderate-sized evergreen fern with delicate fronds. It occurs at higher elevations from Oklahoma to Connecticut, principally in the following physiographic provinces: Interior Highlands, Interior Low Plateaus, Valley and Ridge, Blue Ridge and Piedmont. In Arkansas, it occurs in rocky elevated areas of the Interior Highlands which stretch across the northwestern half of the state. The genus name combines Greek words for “margin” and “flower,” from the marginal sori (fruit dots). The specific epithet describes the pubescence. The common name “lipfern” refers to revolute (turned-under) pinna margins. Its preferred habitat is dry soils on sunny rocky ledges and slopes, as well as in open woodlands.
Hairy lipfern has a shallow, creeping rootstock composed of branching and tightly intermingled rhizomes that are supported by a thick mat of fibrous roots. In spring, closely spaced fronds with nodding apexes emerge from rhizome tips. The slow growing plants gradually expand outward to produce a thick mass of fronds. Fronds curl up during a summer drought but, like the epiphytic resurrection fern, unfurl again with renewed moisture. Fronds remain viable through winter and die the following summer. Dead fronds gradually decay over several years.
Fronds (leaves) are evergreen. Initially light green, with long pubescence on the stipe (petiole) and rachis (midrib), they mature to a medium green, the pubescence becoming light brown, shorter and more scattered. Hairs on mature leaves do not hide the dark purple surface of the stipe and rachis.
Mature sterile and fertile fronds, viewed from above, have the same appearance. The ascending, lanceolate, thrice-cut fronds are 6 to 12 inches long and 1 to 1½ inches wide. Blades tend to be two to three times longer than their wiry stipes. Fronds have up to about 20 pairs of pinnae (leaflets). Proximal pinnae are nearly opposite and widely spaced but become sub-opposite to alternate toward the apex. Short pinnae near the apex are in contact with each other and merge together. Longest pinnae tend to be near the middle of the rachis. The symmetrical pinnae are cut into one to ten pairs of opposite to alternate pinnules (secondary leaflets). Pinnae are to ⅝ inch long, with rounded apexes. Margins of pinnae are revolute so that a narrow continuous lip is formed on the abaxial (lower) surface––the adaxial (upper) surface thus appears flexed-up and the abaxial surface sunken. Both surfaces are sparsely hairy. Veins are obscure.
Fertile fronds, on the abaxial surface, bear clusters of tiny ball-like sori (each sorus a cluster of sporangia) aligned with pinnule margins and mostly concentrated at the lobes. Sori are mostly exposed outside the marginal lip. Sori change from light green to dark brown before becoming golden yellow with spore dispersal in summer. Sori are naked (without covering structures called indusia).
With spores dispersed, the reproductive activity of the “sporophyte” phase of the fern’s life cycle concludes. In the soil, spores germinate to produce a prothallus, the “gametophyte” phase. The tiny prothallus produces sperm and egg. Sperm swim through ground moisture to fertilize eggs that have remained attached to the prothallus. Fertilization produces a zygote that, in turn, develops into a new sporophyte plant.
In a garden environment, hairy lipfern would be a compact plant that would add texture and character throughout the year. It is one of few ferns that grows well in sunny, dry, rocky sites. In a garden, it is not noted for spreading by spores. This fern, once established, survives drought well. It is not favored by deer or rabbits.
Four other lipferns occur in Arkansas: Alabama lipfern (Cheilanthes alabamensis), Eaton’s lipfern (Cheilanthes eatonii), slender lipfern (Cheilanthes feei), and woolly lipfern (Cheilanthes tomentosa). Of these species, the appearance of hairy lipfern is most similar to woolly lipfern. (To make matters more confusing, hairy lip fern’s species epithet means woolly and woolly lip fern’s epithet means hairy.) Hairy lipfern is significantly smaller than woolly lipfern, and has hirsute pubescence rather than woolly pubescence.
Article and photographs by ANPS member Sid Vogelpohl