Appalachian Lady Fern, *Athyrium appalachensis*
Athyrium appalachensis , Appalachian Lady Fern
LEAVES: clustered at the end of subterranean stem; erect; yellowish-green to green; 8-12 inches wide, 16-28 inches long; wide-based triangle in outline; thrice divided ; sub-leaflets (pinnules) shallowly lobed, lobes bluntly pointed; interior sub-leaflets (pinnules) of basal leaflets (pinnae) remain constant in size, are not reduced ; each leaflet (pinnule) has its corresponding upper (acroscopic) and lower (basioscopic) sub-leaflets (pinnules) of similar length. PETIOLES: yellowish-green to green; grooved on the upper surface. SORI: curved. HABITAT: known so far only from Macon County, North Carolina at elevations above 4,500 feet - except where associated with a waterfall; mesic conditions, along a mountain spring in a mature woodland; a woodland edge near a bald; a grassy verge to a bald; beside a waterfall.
1st record: https://www.inaturalist.org/observations/90300543
2nd record: https://www.inaturalist.org/observations/90888195
3rd record: https://www.inaturalist.org/observations/97995288
4th record: https://www.inaturalist.org/observations/127890150
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Flora of West Virginia second edition mentions in description of Athyrium aspleniodes "Forma subtripinnatum (almost tripinnate) has the pinnules so deeply cut as to appear almost tripinnate; the blade is up to 4 dm. broad. Also throughout the state but less common"
@ccantley - Thank you.
@ccantley
It would be nice to
have/see confirmed examples of Athyrium asplenioides forma subtrpinnatum
have ploidy counts of Athyrium asplenioides forma subtripinnatum in comparison to those of Athyrium asplenioides
It has so far been my experience that the thrice-divided Athryium in Macon County occur in distinctly mesic and cool habitats either by high elevation and north exposure, or in a shaded floodplain of a mountain stream at high elevation, or in the spray zone of a huge waterfall. The typical form of Athyrium asplenioides only requires shaded mesic conditions, irregardless of compass direction of slope exposure, or elevation.
It is early days in my understanding of the Appalachian Lady Fern, but for now it seems to me that it really could be something different. I have a sneaking suspicion that it is a relict species.
What is needed is more data, observational and chromosomal and DNA studies.
All I have at my disposal is to record observational information.
C'est la vie*, eh?
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