Bryophytes are the group of plants commonly known as Mosses and Liverworts.
Most people know what mosses are because they come across them growing in their path or on their wall or on their roof. Many people think that moss is just moss, rather like many think grass is just grass, however there are many different species of grass and likewise many species of moss. Mosses have a stem and along that stem they have very small leaves, sometimes they grow flat and sometimes they grow upright, they also have fine hairs which look like roots but in fact are far less complicated and are called rhizoids. Some mosses are very small and grow compacted together so that they look like a miniature green cushion, but were you to gently pull it apart and look carefully at it, perhaps with a lens then you would see the little stem and leaves. The biggest mosses are the Sphagnum mosses which grow in very wet boggy habitats but whilst they may grow to quite a length (50cm) it is only the last few centimetres that are actually alive and active. Perhaps the most robust genus of mosses are the ones known as Polytrichum. Then we have the Liverworts and these are even more primitive, the main difference is in the structure of their spore producing organ, know as a sporophyte, which is more or less just a ball of spores on the end of a fine stalk. Mosses produce a more complex capsule often with a little cap and an opening which has a circle of teeth like structures that serve to ping the spores out and aid dispersal. The liverworts are subdivided into two groups, there are the thalloid liverworts and the leafy liverworts/ The thalloid ones are flat and grow more or less horizontally across the ground, in some ways they resemble a miniature sea weed. As you might expect leafy liverworts have leaves, but they are minute and only one cell thick and arranged along a primitive stem which always grows horizontally as it is so thin and weak that it could not possibly grow upright. So, have I made this group of plants sound exciting? Well I quite like them though I am no expert on identification but I can at least tell you the names of some of them and if you look closely at some of them they are quite beautiful.
I have had some expert help from The British Bryological Society with the identification and as a result what you are now reading is an edited version of my first attempt. It is now very likely that the identification is correct thanks to an expert ( Sam Bosanquet)….just for the record my original identification was about 50% correct and the ones I got wrong were near misses, so not so bad really
So far I have only found one Liverwort at Catbrook wood and that is one called Marchantia polymorpha.
It is a thalloid liverwort but it is one that produces little cups on its surface that help reproduce and disperse the species. These little cups are called gemmae cups or splash cups. They are like little cocktail glasses but without the stem, so they are like inverted cones. In the bottom are little circles of cells called gemmae which are about 5mm in diameter. The idea of this structure is that if a drop of rain splashes into the cup then it will pick up the gemmae and as it splashes back out of the cup these will be carried out and deposited some distance from the original plant. OK not far maybe 5cm but it helps to propagate the species because these little circles of cells will grow into a new plant. Some other plants do a similar thing, Birds nest fungus and some lichens like Cladonia come to mind. Sam Bosanquet says ‘ this is Marchantia polymorpha subsp. ruderalis, which is a ready colonist of burnt ground. Subspecies ruderalis differs from ordinary (but actually much less common) M. polymorpha in the lack of a black line along the middle of the thallus, so it looks more like Lunularia. The clearest distinction from Lunularia is that the gemma receptacles are circular and have a stalk; they are crescent-shaped and stalkless in Lunularia. The photo also contains Funaria (with young sporophytes) as you realised, plus a Bryum species (likely to be B rubens but that would need checking of the rhizoids for ID) and a Dicranella (probably D. staphylina). ‘
In terms of mosses I think there are about 6 different species, some I am quite sure I can identify and others are a bit more problematical, so if you are an expert please do get in touch.
Lets, start with the easy ones first. Funaria hygrometrica, this has colonised the old bonfire sites, where the brash has been burnt off.
It will build up quite quickly over the next year or so but will eventually be overcome by taller flowering plants, particularly Rose bay willow-herb which is already starting to grow. Funaria is a small upright moss and has quite characteristic spore capsules which are pointed and are bent at an angle from the capsule stem.
Polytichum formosum, there are some nice patches of this moss growing particularly along the edge of the wood where it is under some large Oak and Beech trees, I have not seen it in the area of wood which had the pines, perhaps too dark or maybe it does not like pine needles falling on it. There are several species of Polytrichum but I think the one growing in the woods is formosum, it could be P. commune which is a much taller. Either way this is as I said earlier probably the most robust and impressive looking of the British mosses, it is quite a rich dark green and when damp it has nice spiky leaves making it look like little green stars.
Hypnum cupressiforme, is a branching moss, not small and not large, as mosses go, but the most distinctive feature is that the last little leaf at the end of the stem just hooks over, this can have the effect in the right light conditions of reflecting the light so that it looks like there are tiny highlights all over it. This moss will often spread out to form quite a large patch, it also quite likes to grow on something solid so is often found on the lower levels of tree trunks or on old fallen logs. There is another species called Hypnum jutlandicum which is a bit less chunky than H cupressiforme and that may also be present, if you look at the two photos below the right hand one is H cupressiforme and the left hand one is probably H jutlandicum.
Mnium hornum, you pronounce it nium, the first m is silent…. There are a few patches of this moss but it is not that extensive and is often growing mixed in with other species, it is quite robust but sometimes it is rather a dirty green colour.
Now it gets a bit more difficult, and I was not sure about this one but I am informed that ‘it is by virtue of its small leaves indicative of Dicranum/Dicranella/Campylopus, and its relatively small size and the extreme narrowness of its leaves are typical of Dicranella heteromalla.‘ There is quite a lot of this very distinctive cushion moss which is a nice bright green.
There are some what I would describe as ‘feathery’ mosses, there seems to be two types….This one is Eurhynchium praelongum (Kindbergia praelonga), and although some of the shoots look rather messy the one in the centre has the classic flat look with lots of branches sticking out at 90 degrees to the main stem, as do several others. And this one ‘is probably Eurhynchium striatum, but could be a relatively spiky form of Brachythecium rutabulum. These two are easy in their typical forms, but this isn’t a classic example of either so one would need to look at the stem leaf shape for conclusive ID and I can’t make out the details on the photo.they could both be the same species.’ I expect I will find more as time goes by and if and when they produce spore capsules then I should be able to firm up some of the identification but as I said any help with ID is warmly welcomed. If you want more authoritive information on the mosses and liverworts in Monmouthshire or indeed anywhere else in the UK then visit the British Bryological Association web site and whist you are there visit their pages with photos as some of them are absolutely stunning.