Phyllitis scolopendrium var. americanum
|American fern, American hart's tongue fern, Hart's tongue fern, Hart's tonguefern|
|Dawn M. Gerlica and Lindsey Parsons|
The following Participating Institutions are custodians for this species in the CPC National Collection:
The Holden Arboretum
The conservation of Phyllitis scolopendrium var. americanum is fully sponsored.
Dawn M. Gerlica and Lindsey Parsons contributed to this Plant Profile.
Phyllitis scolopendrium var. americanum, or American hart's tongue fern, is the North American variety of a European species that was described in 1753 by Linnaeus as Phyllitis scolopendrium. This variety was discovered in North America in 1849 in Tennessee, and since then has been found in Alabama, New York, Michigan, and Ontario Canada. The American hart's tongue fern differs from its European relative based on several distinct morphological (shorter fronds, fewer indusia, etc. (Fernald 1935)) and genetic features (144 rather than 72 chromosomes (Britton 1953)). (USFWS 1989)
This fern has evergreen, strap-shaped fronds that are lobed at their base. They grow from 5-17 inches long and 3/4 to 1 3/4 inches wide. The green petiole portion of this frond is from 1 to 5 inches (3 to 12 cm) long, with cinnamon-colored scales on its surface. Fronds arise in clusters from short, creeping rhizomes that are themselves covered in cinnamon-colored scales. (USFWS 1989)
Distribution & Occurrence
- New York
This species is usually found growing on or in close proximity to areas underlain by dolomitic limestone (limestone that is high in magnesium). It prefers areas with high humidity (often found near streams or waterfalls), shade, and moist soil. (USFWS 1988 and 1989)
|At the time when this species was listed in 1989: (USFWS 1989)
In Alabama, there were two known populations, both near the entrance of caves, and both on the decline
In Tennessee, only one population was known, with 17 individuals.
In Michigan, four populations were known, two of which were considered healthy and three of which were on protected land.
In New York, as many as 13 populations were known from two counties. Two of these populations, located in a State Park, were the largest known in the country in 1988, supporting 2,657 individuals.
Conservation, Ecology & Research
Commercial/ Residential development
Insect infestations (eat leaves of the above canopy)
Cinquemani Kuehn, D.M.; Leopold, D.J. 1992. Long-term demography of Phyllitis scolopendrium var. americana in central New York. Bulletin of the Torrey Botanical Club. 119: 65-76.
Cinquemani Kuehn, D.M.; Leopold, D.J. 1993. Habitat characteristics associated with Phyllitis scolopendrium var. americana in central New York. Bulletin of the Torrey Botanical Club. 120: 310-318.
Cinquemani, D.M.; Faust, M.E.; Leopold, D.J. 1989. Periodic censuses of Phyllitis scolopendrium (L.) Newman var. Americana Fernald since 1916 in Central New York State. American Fern Journal. 78, 2: 37-43.