Mosses

All images on this website have been taken in Leicestershire and Rutland by NatureSpot members. We welcome new contributions - just register and use the Submit Records form to post your photos. Click on any image below to visit the species page. The RED / AMBER / GREEN dots indicate how easy it is to identify the species - see our Identification Difficulty page for more information. A coloured rating followed by an exclamation mark denotes that different ID difficulties apply to either males and females or to the larvae - see the species page for more detail.

Mosses, liverworts and hornworts are collectvely called Bryophytes. They are small flowerless green plants that reproduce through spores or asexually via gemmae or tubers. Unlike flowering plants, ferns and confider, they have no vascular system (the phloem or xylem vessels of floweing pakltns, ferns, conifers etc.) Instead, water an nutients diffuse directly into their thin tissue. As early colonisers they can be found in virtually all terrestrial habitats. Bare soil, wall tops, tarmac - indeed just about every crevice supports one or more species. As well as being all around us, they are a good option to study in January and February when most other plants and invertebrates are absent.

Facebook Group: Bryophytes of Britain and Ireland

The British Bryological Society provides some excellent online guidance to help identify mosses and liverworts.

The BBS guides to common mosses and liverworts are very useful.

Atherton, I., Bosanquet, S. & Lawley, M. (eds.) 2010. Mosses and Liverworts of Britain and Ireland: A Field Guide BBS is an accessible guide for non-specialists and is highly recommended. The BBS are currently planning a second edition.

Watson, E.V. (1981) British Mosses and Liverworts (3rd edition) CUP has keys that are more technical, based on cell shape and leaf characteristics that may require microscopic examination, but be aware that since it was published, there have been some changes in taxonomy, and some new species have arrived in the Biritish Isles.

To identify some mosses, you may need to look at the microscopic details of the leaves - e.g. the cell shape in different parts of the leaf; whether there is a nerve in the leaf; whether the leaf margin is toothed, etc. For most species, the leaves are just one cell thick, and the shape of cells can be seen at low magnification. The BBS website includes micro-photoographs of the leaves of some species, and the drawings in Watson (ref. above) are very helpful. To begin with you will need to decided if the moss is a Sphagnum, or is acrocarpous or pleurocarpous. See sections below for help with this.

Moss specimens will keep for a long time in paper packets (not plastic) once they have dried out. They re-hydrate very quickly once water is added.

If you know of other websites or books that you would recommend, do let us know: info@naturespot.org

Sphagnum - the bog-mosses

Sphagnum species of moss live in bogs or very wet ground, often associated with moor and heathland. Their structure means they can hold water like a sponge. Because of their chemistry, they decay very slowly and Sphagnum will slowly build up a layer of peat. forming bogs, mires, raised bogs and blanket bogs. These are some of the most important habitats in the British Isles. Their ability to hold water means that the blanketing Sphagnum bogs on our uplands help to regulate water flows and mitigate the impact of heavy rainfall. Conservation and restoration of these habitats, such as on the Peak District in Derbyshire, is a priority in the battle to reduce flash flooding downstream in rivers like the Derwent.

They are very common in upland areas of the UK, but scarce in lowland regons like Leicestershire and Rutland. In our area, a few colonies of a few species survive in wet acidic condiions, such as on the higher parts of Charnwood Forest and in mining subsidence flashes in the former coalfield area of the north-west Leicestershire in mining subsidence flashes.

Individual species are difficult to identify, most requiring careful field notes backed up by microscopic examination. The upright stems are clothed in spirally arranged branches ('fascicles'), forming a compact rosette-like head ('capitulum') at the stem tips. The shape of stem and branch leaves, the microscopic detail of upper and lower leaf surfaces, and stem sections are the characters used most often in identification; under the microscope, the leaves have alternating green and transparent ('hyaline') cells.. The capsule is raised on a short stalk and is ovoid or globular; it is similar across the species. In shade, they are usually green but develop secondary pigmentation in sunlight, often colouring with red, pink or orange tints; this can help in identifying a species. For some species, colour changes can also happen later in the year. The dry out to a pale green, but rapidly re-hydrate and regain their usual coloration.

A useful guide is Godfrey, G. & Rogers, K. (2021) Sphagnum mosses: field key to the mosses of Britain and Ireland. FSC (Aidgap series)

Sphagnales

Acrocarpous mosses

Acrocarpous mosses have a tufted habit of growth made up of separate upright shoots, which are often simple but may be forked or with a few branches, often forming form dense cushions. In most cases the seta bearing the capsule arises from the tip of the shoot.

Polytrichales

The Hair-caps and related species (Polytrichum, Atrichum, etc.) are unusual bryophytes in that the leaves have plates of green tissue overlying the nerve down the middle of the leaf, at right angles to it. This thickening of the central part of the leaf gives them a robust opaque appearance in contrast to the thin, single celled leaves of other mosses.