Licorice fern is a small fern with a surprising address: it often grows on trees. Its creeping rhizome works through the moss on the trunks and branches of bigleaf maple and alder, and it also spreads over mossy logs, rocks and wet banks, sometimes forming mats or sheets. The fronds are simple ladders of narrow, pointed segments, up to a couple of feet long.
Plants that grow perched on other plants this way are called epiphytes. The tree is only a place to live, not a source of food.
Its calendar runs against most plants. Licorice fern goes dormant in summer and its fronds dry out in the heat, which can make it hard to find in midsummer. In the cool, wet months it is green and easy to see.
The common name comes from the rhizome, which botanists describe as having a strong licorice flavor.
Look for it on moss-draped maples and rocks in the low-elevation forests on the west side of the Cascades and in the Columbia River Gorge, where it grows mostly below about 1,800 feet. Winter and spring hikes show it at its best.
How to identify it
Fronds up to about 2 feet long, cut almost to the midrib into a single row of narrow segments with finely toothed edges and sharp or drawn-out tips. Round spore dots sit about midway between the segment edge and midvein. It grows from a creeping rhizome with brown scales, often on mossy tree trunks.
Look-alikes
Western polypody grows mainly on moist cliffs and rock ledges and has shorter fronds, generally under about 14 inches, with blunter segment tips. Licorice fern's segments are longer and more sharply pointed, and it is the one usually seen on tree trunks.
Habitat
Moist, shady lowland forests, on the trunks and branches of bigleaf maple and alder, on mossy logs and rocks and on wet banks. It occurs in the western Cascades and the Columbia River Gorge, mostly below about 1,800 feet.
Sightings in the forest
405 research-grade sightings in Mt. Hood National Forest on iNaturalist, most recently on October 31, 2026. See them on iNaturalist →