Mosses are miniature marvels, almost hiding from us in plain sight. They are nature’s velvet cushions. Their small-scale intricacy is a delight when viewed close-up, as you can see in the photographs below. Globally, there might be 20,000 different species of moss. In Britain, one can find around 760 moss species. In Heene Cemetery, we have identified 19 – all with the valued help of the county recorder for mosses, a bryologist. It is possible that the closer we look, we might find a few more species. This variety is relatively good for an urban cemetery, and is worth exploring simply for what it is.
Mosses can be found practically anywhere. Look up, and you’ll find them on roofs. Scan the walls that you pass as you amble round your neighbourhood, and they’ll be there. Check kerbstones, pavements and tarmac, and you’ll see mosses valiantly clinging on, colonising the tiniest of cracks and fissures in almost any outdoor surface. In the Cemetery one can see them in the grass paths, tucked in the surface of gravel gravestones, and squeezed into the tiniest of cracks between marble and stone slabs. They have colonised small vertical surfaces and been scraped up by birds and mammals. Gusts of wind roll them around like shrunken tumbleweed. Some are like pin cushions, others like green feathers. Many are repurposed by birds to provide lining for their nests. Their total volume is not great yet, when you start looking, they are everywhere. Mosses truly are ubiquitous.
Yet too many of us class them as a kind of weed, one to be raked out of lawns, hosed off roof tiles, eradicated and expelled as undeserving serious attention. How wrong can we be? Think again!
Mosses are ancient non-flowering plants. On this website, they are classed separately from flowering plants. They produce spores, have leaves and stems. Yet mosses do not have roots. Instead of roots, mosses have rhizoids; think of these parts of moss plants as their grappling-hooks, enabling them to adhere to soil, to tree bark, even to rock and – in the Cemetery – to certain types of gravestone.
These tiny plants have adapted to everywhere on the planet where plants can grow. Over millions of years, they have learned to survive – and photosynthesise (just as plants do) – in environments as hot as 40°C and as cold as -15°C. Indeed, scientists have discovered that moss frozen for 1,500 years in Antarctica can come back to life and continue to grow undamaged by the extreme cold there. They can be zombies, albeit ones that harvest carbon dioxide and create the same oxygen that we breathe! Indeed, some estimates suggest that mosses could be contributing 30% of the oxygen that the whole plant kingdom produces.
Mosses also tolerate drought and inundation with equal aplomb. Drench them in seemingly endless downpours and they thrive. Dry them out and they eventually shrivel and go brown. Rehydrate them – artificially or in rain or a heavy dew – and they return to their former verdant glory. One source says that one moss found in the Americas, Anoectangium compactum, can survive for 19 years without water – and then bounce back to life when rehydrated. See! Little, harmless zombies!
The anatomy of mosses
Mosses have stems which in turn have leaves, although all this is in miniature. They also have what we might think of as fruits which emerge from the tips of stems which are called seta. These develop graceful heads which are known as calyptra. The slender stem and the graceful head are known as sporophytes. Spores that develop into new plants emerge from fruiting calyptra. These spores are dispersed by wind, not by pollinating insects. This vocabulary is shown on the following diagram (courtesy of Wikipedia, where you can find more information about this process.)
A gallery of Heene Cemetery’s mosses
To help you appreciate how small these mosses are, a paperclip has been included in some of these photos. You could be forgiven for thinking that this looks like a trombone. Indeed, for French people it is just that – as the French word for paperclip is le trombone. Miniature mosses, remember!
(photographed in the midst of the bulbous heads of White Stonecrop)
A complete list of the mosses in the Cemetery at the time of writing is:
- Bicoloured Bryum (Bryum dichotomum)
- Bird’s-claw Beard-moss (Barbula unguiculata)
- Capillary Thread-moss (Bryum capillare)
- Clustered Feather-moss (Rhynchostegium confertum)
- Common Feather-moss (Kindbergia praelonga)
- Common Pottia (Tortula truncata)
- Common or Great Pocket-moss (Fissidens taxifolius taxifolius)
- Cylindric Beard-moss (Didymodon insulanus)
- Heath Star-moss (Campylopus introflexus)
- Intermediate Screw-moss (Syntrichia intermedia (montana))
- Lesser Bird’s-claw Beard-moss (Barbula convolute convolute)
- Pointed Spear-moss (Calliergonella cuspidate)
- Rough-stalked Feather-moss (Brachythecium rutabulum)
- Silver-moss (Bryum argenteum)
- Springy Turf-moss (Rhytidiadelphus squarrosus)
- Swartz’s Feather-moss (Oxyrrhynchium hians)
- Tender Feather-moss (Rhynchostegiella tenella)
- Violet or Mauve Thread-moss (Bryum ruderale)
- Wall Screw-moss (Tortula muralis)
It’s a bonus that these mosses each have their own English name, many of which accentuate their individual characteristics.
Photographing the mosses in the Cemetery
All of the above photographs – and the many more on the website – were taken inside the Cemetery (except for three, which were brought indoors to escape bad weather). The process of photographing these mosses is an amateur affair done by a volunteer. Here’s a list of essentials for accomplishing this:
- a half-decent DSLR camera; results from even high-quality mobile phones are not always satisfactory
- a true macro lens, in this case one with a focal length of 100mm that has a magnification ratio of 1:1
- an articulating tripod that has an arm that can hold the camera close to the ground; the above photographs were taken with the lens about 4.5 inches away from the subject
- a shutter release cable that allows you to fire the camera without touching it, thus avoiding camera shake
- a copy of Photoshop (or similar) for focus-stacking (see below)
- any weather except rain (unlike when photographing plants, flowers and pollinators, wind isn’t a problem: mosses remain still for the camera!)
- the ability – and willingness – to crouch on the ground
- a degree of persistence – and dottiness!
The county recorder for bryology (the study of mosses, liverworts and hornworts) made a detailed survey of the mosses in the Cemetery in the autumn of 2020. It was not practical for the photography to be done alongside this survey. Both are time-consuming processes which require exclusive access to the ‘air space’ around each moss. Instead, we have occasionally emailed photographs, most of which the bryologist has been able to name (based upon that initial survey). Occasionally, small samples have been posted for hands-on identification – by far the preferred method.
Macro photography results in images with an extremely narrow depth of field, often around a millimetre or two. The crisp, in focus zone is just a single, limited ‘slice’. Everything in front of and behind that slice is fuzzy. There’s a trick to get round this and that’s to take multiple photographs with a minor adjustment of focus, successively shooting the closest part to the farthest part of each moss relative to the camera. These images can then be assembled in Photoshop (or similar software) using focus stacking. This creates a single image that has crisp focus across a deeper depth of field. Photoshop aligns the different images and then blends them together. Sometimes four shots will do the trick, sometimes it’s a dozen.
Viewing the sequence of these photographs (before they’ve been assembled into a single shot) can sometimes reveal the presence of a tiny creature living within a moss. (This is noticeable with lichens too.) Scrutinise any one photograph, and the creature is almost invisible, but flip through the sequence of photos and these tiny creatures become animated into a wild, freeze-frame dance. There’s a high probability that some of these might be tardigrades, also known as moss piglets or water bears, primitive, microscopic, eight-legged creatures that live and graze in the micro-ecosystem that mosses provide. We’ve not yet had a clear enough photograph to verify this and include them in our website database. Not yet.
. . . and the other Mosses in the Cemetery
Not surprisingly, with such a common English surname, there are several Mosses buried in the Cemetery, four to be exact:
- Fanny Moss who was buried in 1926 at the age of 78
- Helena Moss who was buried in 1927 at the age of 67
- Mary Moss who was buried in 1913 at the age of 68
- Matthew Moss who was buried in 1900 at the age of 69
Further reading
There are plenty of websites that provide excellent information about British mosses, but two stand out: Kew Garden’s page about mosses and the British Bryological Society’s website.
Written by Rob Tomlinson
