juniper haircap moss

(Polytrichum juniperinum)

Conservation Status
juniper haircap moss
Photo by Luciearl
  IUCN Red List

not listed


NNR - Unranked

SNR - Unranked


not listed


Juniper haircap moss is a very common and very widespread moss with a worldwide distribution, occurring on every continent including Antarctica. In North America it has been recorded in every Canadian province and in every U.S. state except Texas, Louisiana, and Florida. It is common in Minnesota. It is found in a wide variety of habitats, including upland open woodlands, savannas, sand prairies, roadsides, trail sides, rocky ledges, and creek banks. It sometimes colonizes forest openings following a fire or a blowdown. It grows under full sun to light shade, in dry conditions, on acidic, gravelly or sandy soil, or on thin soil over rock.

Juniper haircap moss is a fairly robust, perennial, evergreen, moss. It grows in tufts and has an upright growth habit (acrocarp). It rises on multiple aerial stems from a horizontal underground stem (rhizome). It is highly variable in size but usually 1916 to 2 (4 to 5 cm) tall. In a rock crevice it may be just (1 cm) tall. In areas where it competes with common haircap moss it may reach 4 (10 cm). It usually forms loose to moderately dense colonies, and often forms extensive patches.

The aerial stems are erect or ascending, unbranched, and densely leafy. They are round and yellowish-brown or reddish-brown,

The leaves are narrow, linear to linear lance-shaped, stiff, and to ¼ (3 to 6 mm) long. They resemble juniper leaves. This is the feature that gives the species its common name. When moist, they are flat, not wavy, and they spread straight out in all directions from the stem. When dry, they are straight, not twisted, and they fold upward against the stem. The base of the leaf forms a sheath that wraps around the stem. The sheath is oblong-rectangular, glossy, and yellowish with transparent margins. The leaf blade consists of a very wide midrib (costa) with a flat portion (lamina) on each side. The costa is prominently arced in cross section. The lamina is dark green or bluish-green. The margins are thin and translucent (membranous). They are mostly toothless but there are sometimes a few teeth near the tip. The lamina folds sharply over the costa, protecting it from drying out, and giving the leaf a glossy appearance. The leaf tip is narrowly pointed and reddish-brown. It is extended but there is no true awn.

The stem, leaves, and root-like structures (rhizoids), together are the gametophyte phase of the moss life cycle. Male reproductive structures (antheridia) and female reproductive structures (archegonia) are borne on separate plants at the tip of the stem. Each is subtended by a rosette of modified leaves. On male plants the flower-like rosettes are yellowish to reddish-green and to 3 16 (4 to 5 mm) in diameter. Sperm is accumulated in the “splash cup” and is dispersed by water droplets. When a sperm lands on the tip of a female plant, it swims down the archegonia to the egg. The fertilized egg produces a spore-producing structure (sporophyte). The sporophyte consists of a foot, which attaches the sporophyte to the gametophyte, a long stalk (seta), and a capsule. At maturity, the seta is stout, yellowish to reddish-brown, and 1316 to 2 (3 to 5 cm) long. When immature, the capsule is round and green. At the end of the capsule there is an opening that is covered with a membranous hood (operculum). The operculum is cone-shaped with a short beak-like projection. The entire capsule is covered with a hood (calyptra). The calyptra is membranous, whitish to light brown, and covered with a felt of densely interwoven, matted hairs. This is the feature that gives the genus its common name. As it matures, the capsule develops a ring around the opening (annulus). At maturity the calyptra falls off revealing a sharply rectangular, reddish-brown to dark brown, to 316 (2.5 to 5.0 mm) long capsule. The annulus forces the operculum to drop off exposing the capsule opening with a ring of 64 teeth. The spores are dispersed by wind.


Growth Form






to 4 (1 to 10 cm)


Similar Species


Dry. A wide variety of habitats, including open woodlands, forests openings, savannas, sand prairies, roadsides, trail sides, rocky ledges, and creek banks. Acidic, gravelly or sandy soil and thin soil over rock. Full sun to light shade






Distribution Map



3, 4, 24, 29, 30.

Janssens, Joannes A., and The Minnesota County Biological Survey, Minnesota Department of Natural Resources, State of Minnesota. County Atlas of Minnesota Mosses. May, 2000.









  Kingdom Plantae (green algae and land plants)  
  Subkingdom Viridiplantae (green plants)  
  Infrakingdom Streptophyta (land plants and green algae)  
  Superdivision Embryophyta (land plants)  
  Division Bryophyta (mosses)  
  Subdivision Bryophytina (moss)  
  Class Polytrichopsida  




Polytrichaceae (haircap moss)  


Polytrichum (haircap mosses)  

Subordinate Taxa






Polytrichum alpestre

Polytrichum apiculatum

Polytrichum juniperinum var. alpestre

Polytrichum juniperinum var. juniperinum

Polytrichum juniperinum var. waghornei


Common Names


juniper hair-cap

juniper haircap moss

juniper polytrichum moss










A moss that grows in cushions or tufts; has an upright growth habit; is usually unbranched or sparingly forked; and has the female sporophytes borne at the tips of stems and branches. Adj.: acrocarpous.



On mosses: a ring of cells around the capsule opening beneath the operculum.



On mosses: A thin cap that covers and protects the capsule and operculum and drops off at maturity.



On ferns: The central axis of a pinna, to which pinnules are attached. On mosses: the central axis (midvein) of a leaf. On insects: The vein on the leading edge of the forewing.



Pale green or bluish gray due to a whitish, powdery or waxy film, as on a plum or a grape.



On plants, the flat portion of a leaf or petal. On mosses, the flat portion of a leaf, not including the costa.



Long, straight, and narrow, with more or less parallel sides, like a blade of grass.



Thin, pliable, and more or less transparent.



On mosses: A lid or cover that covers the opening of a capsule and detatches at maturity. On snails: The horny or calcareous door-like structure that seals opening of the shell.



A filament arising from the lower stem of a moss, liverwort, or alga that anchors it to a substrate.



A horizontal, usually underground stem. It serves as a reproductive structure, producing roots below and shoots above at the nodes.



A stiff, hair-like process on the outer surface of an organism. In Lepidoptera: A usually rigid bristle- or hair-like outgrowth used to sense touch. In mosses: The stalk supporting a spore-bearing capsule and supplying it with nutrients. Plural: setae. Adjective: setose.



The lower part of the leaf that surrounds the stem.









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Didn't see much clubmoss this summer...then the rain came.

    juniper haircap moss      

Alfredo Colon

    juniper haircap moss      

Nancy Falkum

    juniper haircap moss      








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Other Videos
  Polytrichum juniperinum commonly known as Juniper hair cap moss a Bryophyte moss
Near The Nature

Nov 15, 2021

Polytrichum juniperinum
Division- Bryophyta
Class- Polytrichopsida
family- Polytrichaceae
Order- Polytrichales
Genus- Polytrichum
species- juniperinum

  Polytrichum juniperinum, Juniper haircap or juniper polytrichum moss Greece by Theo
Θεόδωρος Φωτιάδης

Apr 7, 2022

Polytrichum juniperinum, Juniper haircap or juniper polytrichum moss

Polytrichum juniperinum, commonly known as juniper haircap or juniper polytrichum moss,[2] is an evergreen and perennial species of moss that is widely distributed, growing on every continent including Antarctica.

Ενδιαφέρον παρουσιάζει η αναπαραγωγή του
Its reproduction is interesting

The stems are reddish with grey-green leaves that have a distinctive red-brown tip.[5] This characteristic allows them to be separated from the bristly haircap (Polytrichum piliferum), a plant that the juniper haircap moss closely resembles. The difference is that the bristly haircap has a clear (white) leaf tip.[6] The leaves of juniper haircap moss are lanceolate and upright spreading when dry, and when moist, wide-spreading. Although their growth form can be varied, they generally grow in thin, interwoven mats, and hardly as closely associated individuals.[3][7] Juniper haircap moss have a well-developed system of tiny tubes for carrying water from the rhizoids to leaves that is uncharacteristic of mosses, resembling the system that has evolved in vascular plants such as ferns, gymnosperms and angiosperms. As a result of this developed system, stems have greater potential for height than in typical mosses.[3]

Juniper haircap moss grows across a wide range of habitats but it is most commonly found on dry, acidic, exposed habitats.[5] It is frequent in areas previously disturbed by fire and logging. Other areas they occupy are mineral soil, humus and rocks, stumps, banks, trailsides and dry open woods.[7] Although Juniper haircap moss is not usually found in moist or wet environments, it has been found growing on moist woods and other moist sites such as streambanks.[3]

It is a dioecious plant, meaning that the male and female gametophytes are on separate plants. Juniper haircap moss have very obvious male and female parts. Male plants are said to be unusual because they continue growing without losing the old male organs.[6] The male plants are very noticeable due to their bright reddish orange modified leaves that form small terminal 'flowers' at the shoot ends.[5] The plant has a gametophyte dominant life cycle similar to other mosses. Water is required for reproduction to take place, to enable the sperm to swim down the neck of the archegonia to reach the egg. Once fertilization takes place, the sporophyte of the juniper haircap moss lives on the female gametophyte, growing out of the archegonia. The sporophyte consists of a foot, stalk, a spore capsule, an operculum, and a calyptra.[3] There are 64 short blunt teeth at the top surrounding the capsule mouth and the hood of the capsule, the calyptra, has long hairs that extends down the entire length of the capsule, hence the name 'haircap moss'.[3][7]

The gametophyte is the dominant life phase in the Bryophytes. The gametophyte produces structures known as antheridia and archegonia, which produce the male and female gametes respectively. Collectively these structures are known as gametangia. While some bryophyte species have gametophytes that produce gametangia of both sexes on a single individual, others have separate male and female gametophytes. The antheridia produce many biflagellate sperm cells, which require liquid water to swim to the egg cell. Archegonia in contrast produce a single egg cell located within a chamber known as the venter.

Medicinal use
The herb is believed to be a powerful diuretic by herbalists.[7] Because it increases urinary secretions,[unreliable medical source?] it is useful in the treatment of urinary obstructions and dropsy, an old term for today's edema, which is defined by medicinenet as the swelling of tissue due to accumulation of excess water. The plant is also considered to be excellent for long term use because it does not cause nausea.[unreliable medical source?] Βικιπαίδεια




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Location: Fairview Twp.

Didn't see much clubmoss this summer...then the rain came.

juniper haircap moss

  Alfredo Colon

Location: Albany, NY

juniper haircap moss

  Nancy Falkum

Location: Kellogg Weaver Dunes SNA, Weaver Dunes Unit


juniper haircap moss







Created: 4/17/2022

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