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spreading wood fern
Dryopteris expansa
Dryopteris expansa, the alpine buckler fern, northern buckler-fern or spreading wood fern, is a species of perennial fern native to cool temperate and subarctic regions of the Northern Hemisphere, south at high altitudes in mountains to Spain and Greece in southern Europe, to Japan in eastern Asia, and to central California in North America. It prefers cool, moist mixed or evergreen forests and rock crevices on alpine slopes, often growing on rotting logs and tree stumps and rocky slopes. It is characteristically riparian in nature, and is especially associated with stream banks.
From the article Dryopteris expansa on Wikipedia (CC BY-SA), quoted section by section
Description
It has a short rootstock. The leaves are with large, green lacy fronds typically 30–120 cm (12–47 in). The petiole is usually about half the length of the leaf blade and brown scaled. The scales are black-ish in the middle. The leaf blade is triangular and sparsely glandular on the underside. The deltate fronds are bipinnate at the base, pinnate toward the apex. The rhizome is erect or ascending, often producing offshoots. Sori occur medially on the underside of the pinnae. Propagation is by spores and vegetatively by division of the rhizome. It is easily confused with the related Dryopteris dilatata (broad buckler fern), differing in the usually smaller fronds, and in the pale brown scales on the frond stem being more uniform in color, rarely having a dark central stripe. It also differs in cytology in having 2n = 82 chromosomes (164 in D. dilatata). Leaves of D. expansa are very similar to those of D. arguta.
At the table
The root contains filicin, a substance that paralyses tapeworms and other internal parasites and has been used in herbal medicine as a worm expellent.
Wikipedia: “Uses”
Where it lives
Recorded sightings
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geo-referenced records in GBIF, from museums, herbaria and field observers.
Drag the globe to turn it. Dots are where records exist, not a range map; darker means more records.
In the stacks
Searching the stacks…
Every page naming Dryopteris expansa in the Biodiversity Heritage Library →
This page is assembled live from iNaturalist, GBIF, Wikipedia, the Source Library and the Internet Archive. It is not yet part of the hand-edited codex. iNaturalist taxon 64055.