Common Haircap
The common haircap (Polytrichum commune) is a tall, stiff moss, up to about 40 centimeters, that forms dense carpets on moors, bogs and damp woods. The name comes from the hairy cap covering its spore capsule.
The common haircap (Polytrichum commune) is a tall, stiff moss, up to about 40 centimeters, that forms dense carpets on moors, bogs and damp woods. The name comes from the hairy cap covering its spore capsule.
🧬 Field Guide Specimen: Open Common Haircap in the CRV Science Field Guide to log the specimen, see its place among the Diaphoretickes lineages in the Cladogram Explorer, and test your recall in the Red List conservation game.
A Moss With Plumbing
Haircap mosses have conducting cells that carry water (hydroids) and sugars (leptoids) up and down the stem, a primitive version of the xylem and phloem of vascular plants. This allows them to grow taller than most mosses.
Gametophyte Dominant
In a moss, the green leafy plant is the gametophyte generation, and the spore capsule on a stalk is the sporophyte, which depends on it. In vascular plants the roles are reversed.
Peat and Cushions
Haircap mosses colonize bare, acidic ground and add to peat in wet habitats. See Peat Moss.
Common Haircap at a Glance
| Property | Value |
|---|---|
| Scientific name | Polytrichum commune |
| Kingdom | Plantae |
| Phylum | Bryophyta |
| Class | Polytrichopsida |
| Order | Polytrichales |
| Family | Polytrichaceae |
| Field Guide group | Diaphoretickes: Plants & Algae |
| Diagnostic feature (Field Guide) | Tall star-like green shoots with no true roots or vascular tissue; hairy hood covers the spore capsule on a long stalk. |
| Group | Bryophytes |
| Conducting tissue | Hydroids and leptoids |