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- Osmunda regalis
Osmunda regalis — royal fern
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Facts
Royal fern is a cosmopolitan species, and may be the only vascular plant found on all seven continents. It is common throughout New England in swamps, shorelines and riparian forests. The fertile pinnae of royal fern rise above the sterile pinnae, looking somewhat like a crown, hence the name.
Habitat
Floodplain (river or stream floodplains), forests, shores of rivers or lakes, swamps, wetland margins (edges of wetlands)
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Leaf divisions
-
- the leaf blade is three times compound (divided into leaflets, which are further divided into leaflets, which are further divided into leaflets), or more
- the leaf blade is twice compound (divided into leaflets, which are further divided into leaflets)
- Plant growth form
- the leaves grow from a rhizome growing at or below the ground
- Spore-bearing leaflets
- the spore-bearing fronds are slightly different from the sterile fronds
- Sorus shape
- there are no sori, or they are concealed in leaf segments or hardened, capsule-like structures derived from a modified leaflet
- Leaf stalk scales
- there are no scales on the leaf stalk
- Leaf stalk hairs
- there are no hairs on the leaf stalk
- Leaf blade length
- 20–150 cm
- Leaf vein tips
- the veins go all the way to the edge of the leaf blade
-
Growth form
- Life form
- the plant is herbaceous and terrestrial
- Life stage
- the plant is visible as a typical leaf-bearing fern (sporophyte)
- Spore-bearing leaflets
- the spore-bearing fronds are slightly different from the sterile fronds
-
Leaves
- Features of leaves
- there are no special features on the leaves
- Leaf blade length
- 20–150 cm
- Leaf blade shape
- the leaf blades are widest above the base, then taper broadly towards the tip (ovate)
- Leaf blade tip shape
-
- the tip of the leaf blade is a sharp point (acute)
- the tip of the leaf blade is rounded
- Leaf blade width
- At least 15 cm
- Leaf divisions
-
- the leaf blade is three times compound (divided into leaflets, which are further divided into leaflets, which are further divided into leaflets), or more
- the leaf blade is twice compound (divided into leaflets, which are further divided into leaflets)
- Leaf lifespan
- the leaves drop off in winter
- Leaf stalk color
-
- green
- red or red-brown to purple or black
- yellow to brown
- Leaf stalk hairs
- there are no hairs on the leaf stalk
- Leaf stalk length
- 128–577 mm
- Leaf stalk relative length
- the leaf stalk is more than three quarters as long as the blade
- Leaf stalk scale location
- there are no scales on the leaf stalk
- Leaf stalk scales
- there are no scales on the leaf stalk
- Leaf stalk vessels
- 1 bundle, U-shaped
- Leaf vein branching
- the secondary veins of the leaf blade branch dichotomously (two equal branches at each branch point)
- Leaf vein tips
- the veins go all the way to the edge of the leaf blade
- Leaflet relative size
- the bottom leaflets are about half as long as, to slightly longer than, the leaflets from the middle of the frond
- Leaflet stalks
- the leaflets are stalked
- Lobe or leaflet length
- 150–300 mm
- Lobe or leaflet pairs
- 2–7
- Lobe or leaflet shape
- the lobe or leaflet is widest below the middle and tapering at both ends; lance-shaped
- Lobe or leaflet width
- 50–150 mm
- Plant growth form
- the leaves grow from a rhizome growing at or below the ground
- final leaf segment margin
-
- the topmost lobe or leaflet of the leaf blade has a smooth or lobed edge
- the topmost lobe or leaflet of the leaf blade has an edge with teeth
-
Place
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- edges of wetlands
- forests
- river or stream floodplains
- shores of rivers or lakes
- swamps
-
Spores or spore cones
- Sorus features
- there are no special features on the sorus
- Sorus shape
- there are no sori, or they are concealed in leaf segments or hardened, capsule-like structures derived from a modified leaflet
- Sporangia location
- the spores cover the surfaces of modified leaves or leaflets
- Sporangium type
- the sporangia are opaque without an annulus and usually without a stalk (leptosporangiate)
- Spore forms
- there is only one type of spore present
Wetland status
Occurs only in wetlands. (Wetland indicator code: OBL)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Maine
- unranked (S-rank: SNR)
var. spectabilis
- Maine
- unranked (S-rank: SNR)
- Massachusetts
- widespread (S-rank: S5)
Subspecies and varieties
Our variety is Osmunda regalis L. var. spectabilis (Willd.) Gray.
From Flora Novae Angliae dichotomous key
2. Osmunda regalis L. var. spectabilis (Willd.) Gray N
royal fern. CT, MA, ME, NH, RI, VT; throughout and common. Wet-mesic to hydric soils of swamps, riparian forests, and shorelines.
1×2. Osmunda claytoniana × Osmunda regalis → Osmunda ×ruggii R. Tryon is an extremely rare fern hybrid known from CT (only two populations, CT and VA, reported from the world by Whetstone and Atkinson 1993). Only vegetative leaves have been seen in the wild. These are twice pinnately divided with sessile leafules (the leaflets of O. regalis are short-stalked). The report of O. ×ruggii from NH by Thorne and Thorne (1989) requires confirmation (photos are stored at VT).