''Polypodium virginianum'', commonly known as rock polypody, rock cap fern, or common polypody, is a small

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...

species of

fern A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes exce ...

native to the

Eastern United States The Eastern United States, commonly referred to as the American East, Eastern America, or simply the East, is the region of the United States to the east of the Mississippi River. In some cases the term may refer to a smaller area or the East C ...

and

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

. It generally grows on rocks and occasionally on tree roots in nature.

Description

''Polypodium virginianum'' is a small

rhizomatous In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow ho ...

with narrow leaves long and wide borne on smooth, scaleless petioles . Leaves are evergreen, oblong and

pinnatifid Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and i ...

with acuminate tips. Large, circular sori are prominently featured on the underside of fertile

frond A frond is a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group. Other botanists allow the term frond to also apply to the lar ...

s in late summer and autumn.

Sporangia A sporangium (; from Late Latin, ) is an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular. Virtually all plants, fungi, and many other lineages form sporangia at some point in their life cyc ...

are intermixed with long brown glandular hairs.

Taxonomy

''Polypodium virginianum'' has several synonyms including: ''P. vinlandicum'' A. Love & D. Love, ''P. vulgare'' L. var. ''americanum'' Hooker, ''P. vulgare'' L. var. ''virginianum'' (L.) D. C. Eaton. It is generally treated as distinct, though some have recommended it is equally well treated as a North American variety of the circumboreal ''

Polypodium vulgare ''Polypodium vulgare'', the common polypody, is an evergreen fern of the family Polypodiaceae. ''Polypodium vulgare'' is an allotetraploid species, believed to have arisen by chromosome doubling of a sterile diploid hybrid between two ferns whic ...

''. This species is an allotetraploid of hybrid origin, the parents being ''

Polypodium appalachianum ''Polypodium appalachianum'' is a fern species native to eastern North America. Sometimes called the Appalachian polypody or Appalachian rockcap fern, it is very similar in appearance to '' Polypodium virginianum''. For years, ''P. virgin ...

'' and '' P. sibiricum''.

Distribution and habitat

''Polypodium virginianum'' typically grows on boulders, cliffs, and rocky slopes and does not need well-developed soil. It is common throughout eastern North America; its native distribution ranges from Newfoundland to

Yukon Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...

south to

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

Alabama (We dare defend our rights) , anthem = "Alabama" , image_map = Alabama in United States.svg , seat = Montgomery , LargestCity = Huntsville , LargestCounty = Baldwin County , LargestMetro = Greater Birmingham , area_total_km2 = 135,765 ...

, and

Arkansas Arkansas ( ) is a landlocked state in the South Central United States. It is bordered by Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, and Texas and Oklahoma to the west. Its name is from the O ...

References

{{Taxonbar, from=Q3007914 virginianum Ferns of the Americas Ferns of the United States Flora of North America Plants described in 1753 Taxa named by Carl Linnaeus