Vascular Plants of North Carolina
Account for Sensitive Fern - Onoclea sensibilis   L.Only member of Onoclea in NC.
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Section 2 » Order Polypodiales » Family Onocleaceae
AuthorL.
DistributionStatewide, though surprisingly has been collected from only 4/5th of the counties in the state.

This is a very widespread Eastern species, present from eastern Canada to northern FL and central TX.
AbundanceSurprisingly, it appears to be increasing in recent decades, or perhaps turning up with the advent of county-level inventories. Formerly only fairly common across most of the state, but currently is frequent to common throughout, other than mysteriously infrequently in parts of the south-central Coastal Plain and Sandhills (for no obvious reason). The relatively low number of counties showing collections in RAB (1968), probably less than half of the 100 counties, is in stark contrast to what is present on the ground in the state now. In part, this is due to botanists getting into more remote areas, but also due to the plant showing up in disturbed habitats.
HabitatThis is a wetland species, primarily of forested habitats. It grows in wooded seepages, damp places in bottomland forests, in wet thickets, brownwater swamps, and partly shaded marshes. Also now being reported from wet meadows and fields, clearcuts, and powwrlines.
See also Habitat Account for General Broadleaf Herbaceous Mires
PhenologyFruits in May and June.
IdentificationThis is a familiar wetland fern, confusable only with one other species -- Netted Chain-fern (Lorinseria areolata). Onoclea is the only species in its genus, and it has two distinct frond types. The sterile frond has a stipe about 1-1.5 feet long, and a somewhat shorter blade that is triangular in overall outline. This blade is pinnate, with 10-12 pinnae only wavy-margined and clearly opposite. The blade averages about 10 inches long and about as wide, and it can be separated from the similar one of Lorinseria by the latter having the pinnae alternate and with margins generally straight-entire with no waviness or shallow lobing. Also, the fertile fronds are quite different from each other. Onoclea's fertile frond is shorter than the sterile one, and the blade consist of a long stipe but short and strongly erect pinnae, brown-colored and with bead-like pinnules, about 5 inches long and 1/2-inch wide. Lorinseria's fertile frond has the pinnae also brown but only ascending and linear in shape, averaging about 4 inches wide.
Taxonomic CommentsThe taxon that occurs in NC is the nominate one -- var. sensibilis.

Other Common Name(s)Bead Fern
State RankS5
Global RankG5
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