These are the lycophytes, ferns and fern allies that are officially listed as rare by the State of Ohio. The county ranges cited (and the status) are taken from the Ohio Department of Natural Resources Rare Plants Page (Note: the state has a habit of frequently changing URLs for pages, none of which changes make sense, so this link may not take you there)..
Three species that possibly should be added to the list are Lygodium palmatum, Selaginella apoda, and Huperzia porophila.
Lycophytes | |||
X | Huperzia appalachiana Beitel & Mickel | Licking County. | A rare species overall. |
X | Isoetes echinospora Dur. | Three collections in Portage County, 1913 and 1919. | Easily overlooked. |
E | Isoetes engelmannii A. Br. | Clark and Trumbull Counties; older collections from Champaign, Mahoning, and Portage Counties. | Easily overlooked. |
E | Lycopodiella marqueritae J. G. Bruce, W.H. Wagner, & Beitel | Geauga, Lake and Portage Counties. | |
E | Lycopodiella subappressa J. G. Bruce, W. H. Wagner, & Beitel | Lucas County. | |
E | Lycopodium lagopus (Laestadius ex C. Hartman) G. Zinserling ex Kuzeneva-Prochorova | Knox county; older records from Ashtabula, Athens, Coshocton, Geauga, Jackson, Portage, Trumbull, and Tuscarawas counties. | Neither this nor L. clavatum are currently known from Athens County. This is not accepted as a species by many botanists, but is included in L. clavatum. |
P | Selaginella eclipes Buck. | Once found in Butler County, population no longer exists. | A more western species, probably still extant in western Ohio. |
X | Selaginella rupestris (L.) Spring | Recent collections from Fairfield, Jackson, and Portage Counties, but current populations not known; old collections from Highland, Hocking, and Licking counties. | This plant can make dense, extensive colonies under the right circumstances. Easily overlooked as a moss. |
Fern Allies | |||
T | Equisetum sylvaticum L. | Ashtabula, Carroll, Geauga, Hocking, Stark, Summit, and Trumbull Counties; older records from Cuyahoga, Lake, Lorain, and Portage Counties. | |
E | Equisetum variegatum Schleicher | Clark, Erie, Greene, Henry, Lucas, Ottawa, Stark and Summit Counties. | |
E | Ophioglossum engelmannii Prantl | Adams County. | Fairly common in limestone areas farther south and west. |
E | Ophioglossum pusillum Raf. | Cuyahoga, Erie, Huron, Lake, Lucas, Portage, and Williams Counties. | A more northern species. |
E | Botrychium lanceolatum (S. G. Gmel.) Angstr. var. angustisegmentum Pease & Moore | Hocking County; old collections from Ashtabula, Geauga, and Portage Counties. | Easily overlooked. |
E | Botrychium simplex E. Hitchcock | Highland County; older collections from Ashtabula, Erie, and Geauga Counties. | Easily overlooked. |
T | Sceptridium biternatum (Savigny) Lyon | Adams, Brown, Clermont, Lawrence, Scioto Counties; old collections from Hamilton and Muskingum Counties. | This plant is not common anywhere in its range. Listed on the state site as Botrychium biternatum (Sav.) Underwood. |
E | Sceptridium multifidum (S.G. Gmel.) Nishida ex Tagawa | Ashtabula, Carroll, Columbiana, Fulton, Henry, Lucas, Mahoning, Medina, Portage, Summit, and Tuscarawas Counties; older records from Cuyahoga, Erie, and Lorain Counties. | Listed on the state site as Botrychium multifidum (Gmel.) Rupr. |
True Ferns | |||
T | Asplenium bradleyi D. C. Eaton | Athens, Fairfield, Pike, and Washington Counties; older records from Adams and Hocking Counties. | The state website states that it often grows in the same habitats as A. pinnatifidum, but this is not true. A. pinnatifidum requires a moister habitat, while A. bradleyi requires a much more acid substrate. This fern is rare or uncommon throughout its range. It was collected from Acadia Cliffs Wildlife Area in western Washington County, but this population appears to have disappeared. |
X | Asplenium resiliens Kunze | Collected once from Adams County; no current population known. | It is a southern species, and is somewhat common in some areas of the south. It generally grows on limestone. |
T | Asplenium ruta-muraria L. var. cryptolepis (Fernald) Wherry | Adams, Greene, Highland and Pike; old collection from Clark County. | This is not a common fern anywhere in its range, requiring a somewhat dry and very weathered limestone substrate, but there are areas where it is frequent. |
X | Cystopteris fragilis (L.) Bernhardi | One old collection from Tuscarawas County. | This is a more northern species, reaching up to Baffin Island in Canada, and is frequent or even common in the northern areas. |
P | Cystopteris tennesseensis Shaver | Adams, Belmont, Columbiana, Coshocton, Delaware, Fairfield, Greene, Highland, Hocking, Lawrence, Licking, Meigs, Monroe, Muskingum, Vinton and Washington Counties; there are old records from Pike County. | The state site cites an old record from Athens County as well, but it has been collected recently from Strouds Run State Park. This species (of hybrid origin) prefers calcareous rocks. |
E | Dryopteris celsa (W. Palmer) Knowlton, W. Palmer, & Pollard | Lorain County. | |
E | Dryopteris clintoniana (D. C. Eaton) Dowell | Ashtabula County; there are older collections from Geauga, Lake, Lorain, Mahoning, Portage and Wayne Counties. | |
E | Dryopteris filix-mas (L.) Schott | Richland and Summit counties. | This is a widespread species in the northern hemisphere, and is quite common in Europe, but prefers a cooler climate than Ohio. |
X | Gymnocarpium appalachianum Pryer & Haufler | Known only from 1908 collections in Wayne County. | |
T | Gymnocarpium dryopteris (L.) Newman var. disjunctum (Ledeb.) Ching | Columbiana, Erie, Jefferson, Lorain, and Mahoning Counties; older collections in Ashtabula, Lake, Licking, Portage, and Wayne Counties. | This is a northern species. |
P | Phegopteris connectilis (Michaux) Watt | Ashtabula, Columbiana, Geauga, Harrison, Hocking, Jackson, Knox, Lake, Mahoning, Medina, Portage, Richland, Summit and Trumbull Counties; older records from Cuyahoga, and Lorain Counties. | This fern is known from the Hocking Hills, with populations just east of the rock-climbing area and at Rock House section of Hocking Hills State Park. |
T | Pleopeltis polypodioides (L.) E.G. Andrews & Windham | Adams and Hocking counties; old collections from Clermont, Gallia, Hamilton, Highland, and Meigs Counties. | This fern is a more southern species that is abundant in the far south, but reaches the very north end of its range in Ohio. Recently, a healthy population was discovered in western Washington County, which may be the second-most northern population. |
E | Pteridium aquilinum (L.) Kunth var. pseudocaudatum (Clute) Heller | Three pre-1970 specimens: Jefferson, Meigs and Scioto Counties. | This is actually a widespread and frequent species in the state; it is only this variety that is rare. Some regard this as a species in its own right rather than a variety. |
E | Trichomanes boschianum Sturm | The state site states that this is known only from a single drainage system in Hocking County, but it is also known from Jackson County. | |
X | Woodsia ilvensis (L.) R. Br. | The species was collected twice in the late 1800s in Lake County. | |
P | Woodwardia areolata (L.) Moore | Adams, Ashtabula, Athens, Clermont, Cuyahoga, Gallia, Hocking, Huron, Jackson, Lawrence Meigs, Seneca, Scioto, and Vinton Counties; one old collection from Lake County. | This species actually appears to be greatly increasing in southeast Ohio, avidly colonizing old acid mine seeps. |