These are the lycophytes, ferns and fern allies that are officially listed as rare by the State of New Hampshire. The information is taken from the New Hampshire Division of Forests and Lands, Natural Heritage Bureau's Rare Plant List for New Hampshire.
| G1 S1 | Critically imperiled because extreme rarity (generally one to five occurrences) or some factor of its biology makes it particularly vulnerable to extinction. |
| G2 S2 | Imperiled because rarity (generally six to 20 occurrences) or other factors demonstrably make it very vulnerable to extinction. |
| G3 S3 | Either very rare and local throughout its range (generally 21 to 100 occurrences), or found locally (even abundantly at some of its locations) in a restricted range, or vulnerable to extinction because of other factors. |
| G4 S4 | Widespread and apparently secure, although the species may be quite rare in parts of its range, especially at the periphery. |
| G5 S5 | Demonstrably widespread and secure, although the species may be quite rare in parts of its range, particularly at the periphery. |
| GU SU | Status uncertain, but possibly in peril. More information needed. |
| GH SH | Known only from historical records, but may be rediscovered. A G5 SH species is widespread throughout its range (G5), but historical in New Hampshire (SH). |
| GX SX | Believed to be extinct. May be rediscovered, but evidence indicates that this is less likely than for historical species. A G5 SX species is widespread throughout its range (G5), but extirpated from New Hampshire (SX). |
| A | global rank |
| B | state rank |
| C | federal listing |
| D | state listing |
| E | known sites before 1993 |
| F | known sites 1993 and after |
| Species | Common Name | A | B | C | D | E | F |
True Ferns | |||||||
| Asplenium rhizophyllum | walking spleenwort | G5 | S1 | -- | E | 5 | 1 |
| Cryptogramma stelleri | slender rock-brake | G5 | S1 | -- | E | 3 | 3 |
| Diplazium pycnocarpon | narrow-leaved glade fern | G5 | S1 | -- | E | 3 | 3 |
| Dryopteris filix-mas ssp. brittonii | male wood fern | G5T4? | S1 | -- | E | - | 1 |
| Dryopteris fragrans | fragrant wood fern | G5 | S2 | -- | T | 5 | 10 |
| Lygodium palmatum | American climbing fern | G4 | S1 | -- | E | 3 | 2 |
| Pellaea atropurpurea | purple cliff-brake | G5 | S1 | -- | E | - | 1 |
| Trichomanes intricatum | Appalachian bristle fern | G4G5 | SH | -- | E | 2 | - |
| Woodsia glabella | smooth cliff fern | G5 | S1 | -- | E | 2 | 2 |
| Woodsia obtusa | blunt-lobed cliff fern | G5 | S1 | -- | E | 4 | 5 |
| Woodwardia areolata | netted chain fern | G5 | S1 | -- | E | 3 | 1 |
Fern Allies | |||||||
| Equisetum palustre | marsh horsetail | G5 | S1 | -- | E | 10 | 2 |
| Ophioglossum pusillum | northern adder's-tongue fern | G5 | S1 | -- | E | 1 | 3 |
Lycophytes | |||||||
| Isoetes acadiensis | Acadian quillwort | G3Q | SH | -- | E | 3 | - |
| Isoetes riparia var. canadensis | Canada shore quillwort | G5?TNRQ | S1 | -- | E | 12 | 3 |
| Isoetes engelmannii | Engelmann's quillwort | G4 | S1 | -- | E | 14 | 1 |
| Isoetes lacustris | lake quillwort | G5 | SH | -- | E | 5 | - |
| Lycopodiella appressa | appressed bog-clubmoss | G5 | S1 | -- | E | 1 | 1 |
| Lycopodiella alopecuroides Bog | foxtail clubmoss | G5 | S1 | -- | -- | - | 1 |
| Huperzia appressa | mountain firmoss | G4G5 | S1 | -- | E | 11 | 3 |
| Huperzia selago | northern firmoss | G5 | SH | -- | E | 3 | - |