Sunday, 19 October 2025

Elm

July 2025. A hot field with wildflower mix is sweltering in South Suffolk sunshine. The clay-rich topsoil has cracked over the past few weeks of drought. Foraging bees lend a desultory drone. Nearby, an ancient woodland is inviting us out of the heat, but we will need to struggle through fallen twigs, branches, grass tussocks and nettles and beneath its leafy skirts to enter there.

Inside, the vista expands into an ample space of hard trunks and lofty limbs; zones of light and shade; those myriad green flakes we call leaves clustering in aerial mosaic overhead.


The elm tree is very large and correspondingly old - evidently it is a remarkable survivor.  The lofty elms of my childhood have gone; only their clonal regrowth reminds us where they were before the bark beetle finds them and they die off after about 20 years. Their desiccated skeletons rattle in East Anglian hedgerows for a decade or so before rotting away. Meanwhile another generation of suckers is reaching for the sky. This elm is different:  it has inbuilt disease resistance which makes it a desirable variety - potentially a variety with a destiny. 

We are here for look for elm seeds. Emerging into a clearing packed with waist-high bracken and nettles, we can examine the branches of this venerable old tree to find clusters of petalloid seeds on twig tips. There aren't any to speak of - the tree has taken shock at the drought and dumped its children.  They lie like papery, brown farthings underfoot among the leaf litter. I have to pick up and bag handfuls of debris to get enough of them. 


The elm seeds contain an invisible message packed in their DNA.  Once they begin unpacking it, we hope they will grow into disease-resistant Ulmus laevis. With a bit of tree nursery help, we hope to spread them elsewhere in Britain. I will never see them grow great in my lifetime but perhaps a little fiddling labour now sorting through a bag of papery seeds is a gift to an uncertain future which others will enjoy, just as I enjoyed the towering elms of my Suffolk childhood. 

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Text and images © Tim Holt-Wilson, 2025



Rewilding Cringleford

Cringleford is a Norfolk village lying about two and a half miles distant from the city centre of Norwich. It is an affluent suburb close to the university and hospital, and lies sandwiched between the Yare valley and the city’s southern bypass. Its remaining arable fields are ripe for development. 

About a decade ago the slow process of converting farmland into premium housing estates began. Access roads were inserted and three-bed houses built in streets with names like Dragonfly Lane, Chervil Close and Nightingale Drive. Everyone wants a bigger house with a double garage, and everyone also wants green space and access to nature.

Round House Way serves these estates and either side of it lies an area of green space. An aerial photograph on Google Maps shows a mosaic of bushes and grassland grown on land tumbled down from arable.

Round House Way, courtesy Google Earth Image @ 2025 Airbus

This ‘self-willed’ habitat has taken twenty years to develop its intricacy on what is essentially a housing company land-bank. But time has been called on this natural growth. This year the western side was swiped and shredded to ground level, in preparation for redevelopment [photo 1]. 

1. Round House Way West, looking south (October 2025)


The eastern half remains. People might say “it’s derelict, it looks a mess - it’s a wasteland”. 

But what we find east of Round House Way is scrub land with a richly biodiverse fauna and flora – fruit of two decades of chance, natural elaboration. [photos 2 & 3]  An architecture of hawthorn, blackthorn, oak, rose, willow and bramble frames a herb-rich sward bumpy with anthills and the myriad craters of ground-nesting bees. A solitary cat ranges out from nearby houses, captivated by vole and shrew. Goldfinches flit among seed heads of teasel. Foxgloves and St John’s Wort star the grass. Toadstools shoulder up through the remnants of last-year’s matted vegetation. Processes of seed-time and decay are running their natural programmes at ground level; the loamy soil is bouncing back from the decades of agricultural treatment received from insecticides, herbicides and fungicides. Autumn is displaying a complex of yellows, browns, reds, russets and greens – falling leaf debris making the foundations for a future nutrient hoard. This land is owned by a housing company. 


2. Round House Way East, looking east (October 2025)













3. Round House Way East, looking south-west (October 2025)















The planet is in a Biodiversity Crisis. How can we turn local development into an engine for restoring biodiversity? It requires political will at national and local level, and buy-in from the building companies. If an environmental impact assessment has been carried out at Round House Way it will have assessed impact on a set of prescribed species, but ignored the cumulative value of allowing a self-willed ecological community to develop true biodiversity over a twenty-year span.  A real natural asset has grown up and could be incorporated into local Green Infrastructure if the political will – and awareness – were there.

But soon the flail mowers will move in soon and all this biological richness will be obliterated. A new ground-zero will be set – but a greatly impoverished one.

I am not really asking for protection of the site – arguably any patch of land on this soil type in Cringleford could develop such biodiversity over a twenty-year time-span. I am asking for the biodiversity of such scrub lands routinely to be recorded and then evaluated in terms of their actual - and potential – assemblage value as ecological hotspots and corridors, and for this information to be translated into the planning process. I want all of this site’s biodiversity to receive greater consideration than the usual ecological consultants’ reports. This would require evaluation of the diversity of plants and invertebrates and not just vertebrates (Morris & Welch, 2023). The very early stages of abandonment of arable land can be highly productive for invertebrates (Fuller & Freeman, 2025). 

We know that scrub habitat is ecologically valuable. See, for example, a recent JNCC report which was written to inform government decision making (Mortimer et al, 2000). Scrub does pose challenges for practical management due to its successional nature, but its biodiversity value is absolutely clear. If there is a will to manage it properly it can revitalise the natural assets of urban and peri-urban areas such as Cringleford. It could be part of the invaluable reservoir of biodiversity which ensures the resilience of our nature networks in the face of climate change as well as the increasing pressure of human settlement. Scrub should be understood as contributing vital Green Infrastructure to development projects – provided it can be recognised and properly valued in terms other than financial ones. Round House Way East is a parish asset.

For example, a play area for children; a foraging terrain for birds; a place to go blackberrying and collecting sloes; a cherished wilderness; airspace for bats to hunt moths; a resource for dog-walkers and bird-watchers; a secure place to dig a nest burrow. [photo 4] Round House Way East is a former arable field which is busy rewilding. Can we support that process for future generations of humans, plants and animals? 

4. An Ivy Bee (Colletes hederae) bringing back pollen to her nest hole at Round House Way East (October 2025)
















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References

Fuller, RJ and Freeman, G (2025). Letting nature take back control: a paradigm shift in UK nature conservation? British Wildlife, 36.8, pp547-554.

Morris, RKA and Welch, MD (2023). Is invertebrate conservation in Great Britain best achieved by policies that increase species protection? Journal of Insect Conservation, 27(4).

Mortimer, SR et al. (2000). The nature conservation value of scrub in Britain. Report #308, Joint Nature Conservation Committee, Peterborough.

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© Tim Holt-Wilson, 2025


Thursday, 19 May 2022

No-Mow-May

May returns and “the voice of the turtledove is heard in our land”. Sadly, the voice of the lawnmower is more likely to be heard today, as the grasses, dandelions and daisies surge ahead, and normalising lawn management fires up again. A lawn is a meadow passed under the yoke of culture. For some people even a striped lawn is too wild, and they replace it with plastic green turf. All this ‘normalising’ comes at a cost to the diversity of living things which thrive in grassland. 

Grasses were invented by nature about 120 million years ago, though it is unlikely that dinosaurs ever rolled on a prairie. It would take 70 million years or more before grasses were prolific enough to carpet the ground, so the pleasure of rolling on a greensward belonged to browsing and grazing mammals of the early Tertiary epoch. Later, whole ecosystems such as savannah, steppe and pampas evolved as a joint project of mammals and grasses. Grazers such as aurochs are likely to have maintained forest clearings and floodplain grasslands in prehistoric Britain (Yalden 1999, p.72). Wrested from woodland and valley scrubland for the purpose of livestock farming, hay meadows and grazing pastures are a Neolithic creation (Rackham 1987, p.330). Sheep, cattle and horses need them, and we need these animals.  

The familiar British meadow has become a rarity, particularly in the lowlands where 90% of it has been lost in the past century (Lake et al, 2020, p152). Ploughed up in favour of arable or replaced by monocultural grass leys, too many old meadows and pastures have been deleted from the landscape and, along with them, the vibrant populations of herbs, insects, birds, mammals, fungi, et cetera,  which had thrived on them for many hundreds of years.

One place in Suffolk with long-established grassland was Brome Park. The Hall was built in Tudor times, about 1550, and an engraving dated 1707 shows the house surrounded by extensive parkland and trees. The Park survived until about 1963 after which it was converted to arable land. The only areas not ploughed up were the grounds of the Hall, its tree-lined avenue and a scrap of land attached to a cottage known as The Bungalow, which is where I have lived since 1992.

Brome Hall, illustrated by Jan Kip, 1707.
The site of the Bungalow is just out of the picture, beyond a pond and dovecote (far left).


At first I mowed the lawns assiduously, to keep on top of the vegetation in a drive for order. I was worried what the neighbours might think if I didn’t. Later, led by a mixture of laziness and botanical curiosity, I began to make a first cut much later in the season. I began leaving some areas of grass longer than others – frankly, I hadn’t the heart to mince up the flowers that began showing themselves. As years went by, the lawn began to lose its carpet-like quality and became more like a meadow, with a tussocky grass structure interleaved with a variety of other plants. Some patches were left longer than others, following a three-tier regime. I became aware of the diverse flora within my care. I noticed discrete populations in different parts of the lawn: stands of cocksfoot grass and common sorrel on brown soils contrasting with timothy grass, ground ivy and mosses on sandier soils.


Germander speedwell (Veronica chamaedrys), ground ivy (Glecoma hederacea) and creeping buttercup (Ranunculus repens) in a sward of springy turf moss (Rhytidiadelphus squarrosus), May 2022.


Lady's smock (Cardamine pratensis) starring the lawn, with a large anthill (right), May 2022.




Twayblade orchid (Listera ovata), May 2022.

In 1999, I began making a list of as many species of plants and insects as I was able to recognise. I counted seven species of grass and two kinds of speedwell. I was amazed to find a twayblade orchid in one place and a spotted orchid in another; my lawnmower had never given them a chance to grow before. I found an incipient anthill beneath a plant pot, with yellow meadow ants scurrying about. I replaced the pot, and later discovered they had earthed up around it. This gave me the idea of encouraging anthills, of which I now have four – the largest is 30 cm high x 70 cm across. The lawn is now a texturally rich habitat: it may look a bit ragged and untidy in places but it now supports a much richer flora and fauna. In August I notice small moths flying up from the grasses round my feet. Frogs shelter beneath cool, matted tussocks, and voles forge a complicated network of tunnelled pathways. The spotted flycatcher swoops from a vantage point to snatch flying insects.  The green woodpecker bangs away at the ant hills. Rabbits scuff holes and leave scatterings of bare earth which are host for fresh seeds. Plumes of gnats dance overhead, sometimes following my head disconcertingly as I move about. 

Ant activity amid leaves of creeping cinquefoil (Potentilla reptans) and tufted vetch (Vicia cracca), May 2021.  


Having this meadow on my doorstep has transformed my engagement with and understanding of wildlife, particularly plants and insects. It has prompted photography, microscopy and the gathering of a small reference library. 

What I have done here is allow the inherent richness in this small corner of Suffolk to express itself. The diversity - the seven species of grasses, for example – is a legacy of the past, and argues for habitat continuity here. I didn’t plant them. I argue that my lawn is the final, biodiverse remnant of the old Brome Park which goes back to Tudor times, at least. The sward reminds me of old churchyards; it may never have been ploughed. None of the other land round here – not even the grounds of the Hall – is anything like so rich. I admit of having made additions to the garden over the past 30 years, for example alexanders, hyacinth, marjoram, lungwort, mahonia, box, magnolia, and – on the lawn – a clump of greater knapweed. I argued that none of these have modified the baseline plant population, which I think is an ancient one. I fear that when I leave here this little world will be endangered by someone who does not appreciate just what a special place it is.

Common sorrel (Rumex acetosa) and fading leaves of lesser celandine (Ficaria verna), May 2022.


My advice to gardeners is to stop mowing in May and see what comes up on your lawn. See what plant and animal diversity you already have – get to know and identify it, discover it close up; take macro photographs. If you find a monoculture then by all means diversify it, with native species chosen to typify a Suffolk meadow in your corner of the county. Someone in the future will thank you. Vary your mowing regime – I use a hand scythe in July to cut the longest grasses in the centre of the lawn while carving out swathes of different lengths in other parts with a petrol lawnmower. Sit back and note what happens. Give yourself a decadal timescale. Prepare to be surprised and delighted by what you find. Remember: it’s not all about ‘you’: the world is a fabric of other lives, from slugs to hedgehogs, frogs to daisies, and your lawn is part of the tapestry which makes theirs possible. Make space for nature, and remember that there is nowhere on Earth that we can take wildlife for granted any more. You have a scrap of our planet in your care.

A small hay meadow in the making - first growth of grasses Alopecurus pratensis, Arrenatherium elatius, Dactylis glomerata, Lolium perenne, Poa trivialis, Poa pratensis and others, May 2022



REFERENCES

Lake, S. et al 2020. Britain’s Habitats. Princeton University Press.

Rackham, O. 1987. The History of the Countryside. J.M. Dent & Sons Ltd.

Yalden, D. 1999. The History of British Mammals. T & AD Poyser Ltd.



Thursday, 17 March 2022

In memory of a friend

Grief comes as a sudden surprise, like a sudden shower in May, and I remember you.

I never imagined this day would come - you, strong as a horse, brave as a bear - you now underground, and all my crowding memories in your stead: the places we saw, the times we had, our expeditions, which were always purposeful adventures. You had a way of condensing action, like a lens with the rays of the sun; of gathering purposes from a frayed spray of ideas; seizing an idea then running with it - to chaos or glory, failure or success.

You inherited your father Adam's instrumental, but slightly unhinged and experimental, approach to life. Mythic passion was your driver. You're the sort of man who'd cut his way through forests, axe in hand with tinder & flint in his pocket. You'd climbed trees in order to see further, like Strider scouting a way through Mirkwood. You'd know how to play a tune on a hand-made whistle or squeeze drinking water from moss. You are just the sort of man I'd want in my tribe. Your passion spanned trees and songs, handicrafts and tools, hounds and gunpowder. 

  • Remembering that time at Hellions Barton when we made a bomb and pushed it deep into the clay of a river bank. When it went bang and after the smoke and spray had cleared we found we had almost dammed the stream. 
  • Or trespassing into the gloomy woods at Heyford Hall on Dartmoor, where Arthur Conan Doyle got his inspiration for 'The Hound of the Baskervilles'. Setting up sheeps' skulls on a row of stakes. "What are you doing on my land"? the man demanded to know "Just doing some Ju-Ju, sir!", replied Jonathan coolly, "Well clear orff and take those bloody skulls with you".
  • New Year, 2015, with Bede and Beaumont in the South Downs, treading in the footsteps of Edward Thomas, climbing up through a slippery chalk wood, with badger setts and prehistoric flint flakes under foot; each tree a storied thing, a bearer of tales or, potentially, timber. 

Your generosity. When I was ill you drove 175 miles - and back - to bring me a load of fire wood.

I cannot understand how all your strength has been laid low. Who was your foe: a treacherous branch, or your own brave inattention? Whatever, the wood elves have taken you for their own, my friend, and you have gone with them into the West.

We find ourselves standing here, alone in the Grey Havens, humming our wistful songs.


I sit beside the fire and think
of all that I have seen
of meadow-flowers and butterflies
in summers that have been;

Of yellow leaves and gossamer
in autumns that there were,
with morning mist and silver sun
and wind upon my hair.

I sit beside the fire and think
of how the world will be
when winter comes without a spring
that I shall ever see.

For still there are so many things
that I have never seen:
in every wood in every spring
there is a different green.

I sit beside the fire and think
of people long ago
and people who will see a world
that I shall never know.

But all the while I sit and think
of times there were before,
I listen for returning feet
and voices at the door.



You are forever in my heart, my friend. You are gone with the stars. You are off rolling, like Beaumont, with Orion. I know one day I'll join you.


In Memoriam Jonathan West

Monday, 14 February 2022

Carstone and Chalk

'Carstone I will mention in order to abuse it" 

(Jacquetta Hawkes ('A Land', 1951).


Why not? This orangey-coloured Norfolk sandstone does not look attractive on its own nor does it combine attractively with other materials. It presents a burning, gingery face to the world and does not weather gracefully. It outcrops between Hunstanton and the Nar valley, where several quarries - such as Snettisham and Middleton - specialise in producing blocks of 'big carr' for masonry or 'small carr' for hardcore or shillet walling.  


The Carstone is at its finest and boldest in the famous geological layer-cake of Hunstanton Cliffs. It underlies the Red Chalk and Grey Chalk and forms a sort of solid biscuit base for those more mellow, pastel layers. Its only fossils are worm burrow traces, and it is laced with liesegang rings: patterns of dark and light cementation brought about by migrating iron compounds. Here, it looks like a sort of industrial slag. 



The only way the Carstone can achieve aesthetic lift-off is probably as a crude pigment. It is so gritty that its iron oxide is a chore to extract for creating home-made paint, but its bold, uncompromising colouration lends itself to astonishing, disharmonious juxtapositions in the landscape. At outcrop it colours the soil a rusty brown and on Hunstanton beach it yields a brown, exotic-looking sand. Hawkes called its effects 'strident': sometimes stridency is needed to shock us out of our visual complacency. Consider this photograph taken in the Snettisham Carstone Quarry.   

Image courtesy Frimstone Ltd

Grey Chalk is as different from the Carstone as cheese. It is indeed it looks like a type of moon-cheese, with a glimmering and dulcet milkiness which is readily ground into lime and - in the right circumstances - can be cut into blocks of stone known as clunch. The Grey Chalk and overlying White (Upper) Chalk span over 40 million years of time. They were deposited on the seabed in a world which was much hotter than our own and had a much higher percentage of atmospheric carbon dioxide. Hawkes calls the Chalk the 'prime creation of later Cretaceous times'. Indeed, the carbon dioxide went into the skeletons of countless billions of planktonic marine organisms whose lime-rich remains rained down through the water and were laid down as calcium carbonate mud. The Chalk now forms ancient seabed deposits as far afield as Russia and Kansas as well as the White Cliffs of Dover. 

Hillington Chalk Pit.
Image courtesy West Norfolk Lime Ltd

Unlike the White Chalk, the Grey Chalk does not contain flints. Instead, it has a variety of body fossils such as echinoids and bivalves and is composed of various horizons of harder or softer texture. It has been extracted in a series of quarries along its outcrop, as at Gayton and Hillington. Where they intercept the groundwater, flash ponds may result on the quarry floor and surprise the eye with a tropical turquoise-blue. 

Hillington Chalk Pit.
Photo with acknowledgements to West Norfolk Lime Ltd
.

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Some thoughts towards 'EXTRACTION : ART ON THE EDGE OF THE ABYSS' at Groundwork Gallery, King's Lynn, 2021.




Tuesday, 11 May 2021

Insatiable

About five years ago I came across the painting 'Insatiable' by Theodore Bolha and Chris Davis. 

It graces the cover of 'Climate Change, Capitalism and Corporations: Processes of Creative Self-Destruction by C. Wright and D. Nyberg (Cambridge University Press, 2015). 

This painting sums up the reason I do what I do, and sums up what I want to say to the people of today and of the future. 

It speaks to me - as I believe it speaks to anyone who has a heart.


The ecological crisis is a profound crisis of meaning and value. 

Dealing with it is the greatest task of our time. 

Sunday, 10 May 2020

Ferment

The garden is - as ever - a wealth of life: a ferment of greenery and flies, birds and song, sunlight patterns on leaves: myriad changes in which each moment is entirely and absolutely different from any other in the world's story. 

Here is my key point: the ceaseless difference at the core of existence: the ever-new.



Were there ever to be a recurrence it would surely signal the end of this world. 

There are repeat elements, for instance the nodding of a branch in the wind, the structure of the song-thrush's call, the form of a daisy flower. But this all happens within the frame of the phenomenal present, which is a process of ceaseless self-differentiation. Every instant is utterly new in detail, unrepeatable.

Monday, 4 May 2020

Clinging On

As the human world reels under the malign influence of Coronavirus, my thoughts turn to Cretaceous barnacles. 

This sudden interest in extinct cirripedia is prompted by a paper published a month ago by Professor Andy GaleNew thoracican cirripedes (Crustacea) from the Cretaceous of Europe and North Africa.[1] It announces the discovery of new extinct genera and species of barnacle. There are two sorts: the acorn/wart-type (sessile) barnacles familiar from rocky shores and the stalk-type (pedunculate) 'goose barnacles' sometimes found attached to drift wood. 


I have never really thought about these crustacea before. They are easily overlooked - that is until you gash your hands or feet on them at the seaside, or eat them in a Portuguese restaurant. What crystallises my interest in them now is that one of the Zeugmatolepadid family now bears my name: Subsecolepas holtwilsoni. It is a lepadid barnacle - one of the stalked type. My thanks go to Andy for the honour. I think i
ts taxonomic status is:
Phylum - Arthropoda
Clade - Mandibulata
Clade - Pancrustacea
Subphylum - Crustacea
Class - Maxillopoda
Infraclass - Cirripedia
Superorder - Thoracica
Order - Pedunculata
Suborder - Scalpelliformes
Clade - Thoracicalcarea
Family - Zeugmatolepadidae
Subfamily - Martillepadinae
Genus - Subsecolepas
Species - holtwilsoni 
Andy Gale is one of a very small band of palaeontological researchers active in the field of fossil cirripedes. Their most illustrious forebear is Charles Darwin. Thomas Withers was active from 1910 to the 1960s, and catalogued the fossils specimens at the Natural History Museum, London. " There can be no doubt the Wither's 'Catalogues' are to fossil lepadomorph and verrucomorph barnacles what Darwin's 'Monographs' are to Recent barnacles."[2] Andy has been one of the most prolific cirripede researchers in recent decades, focusing on the Cretaceous Chalk and publishing many papers. He says that S.holtwilsoni is common in chalk of the Upper Campanian stage in the UK, and that 400 fossil specimens have been found at various old pits in the Norwich area. He named it after me for helping him dig in these pits and for having been involved in their conservation, including Keswick, Catton, Cringleford and Whitlingham.

Collecting samples at Keswick, 2015


I have not visited any chalk pits lately. Britain today is in emergency 'lock-down', and I feel sorry for city-dwellers cooped up in flats and terraced houses. At least I have an extensive wildlife garden to ramble in, and I also enjoy exploring the meaning of our geological heritage.

Crustaceans of the Campanian seas are a great imaginative diversion - a dépaysement, as the French say. Geology and palaeontology call us out of our own time and down into the profound depths of planetary and biological evolution. I try to imagine the lifeworld of the extinct species that now bears my name.  


Here are photos of the type specimens of S.holtwilsoni, variously sourced from chalk pits at Keswick and Cringleford, and all are now archived in the Natural History Museum. They show elements of the set of hard, calcareous plates which enclose the head of the barnacle. 



Type specimens of Subsecolepas holtwilsoni. Image courtesy Andy Gale [1]



Stalked barnacles from JG Wood: 'The Illustrated Natural History'; Routledge, London, 1863

Darwin's drawing of a Middle Jurassic stalked barnacle Pollicipes concinnus,
as found attached to the shell of an ammonite.[3]


Contemporary stalked barnacles attach themselves to floating objects, particularly driftwood, turtles and ships. According to Andy Gale, S.holtwilsoni and other Zeugmatolepadids probably had a similar lifestyle, attaching to the shells of free-swimming ammonites and seabed-dwelling inoceramid bivalves as well as floating wood.[1, p.245] There must have been a steady rain of their plates falling into the carbonate-rich mud of the sea floor, perhaps 100 to 500 metres down.[4] 

The Campanian stage spans from 83.6 to 72.2 million years ago.[5], and chalk of this age is well-represented in Norfolk and Suffolk. I have visited many quarries of this period in the Gipping valley and Norwich areas. At Keswick and Cringleford I helped clear the chalk exposures so that Andy Gale could record the geological succession and take samples. The samples are treated with glauber's salt and freezing in a repeat process until the miniscule fossil fragments - echinoid spines, bits of coral, fish scale, shell, etc - are freed from their chalky matrix and can be examined under a microscope.  


Fossil residues from the Chalk (40x magnification)
  
The contrast between the physical reality of an old chalk pit, with its crumbly, scrub-infested chaos, and the clarified world of knowledge compiled by over 150 years of scientific research into the Chalk is remarkable. We now know much about the Earth's geography during the Campanian, for example that Europe was an archipelago of islands.[6] We know much about biodiversity and details of climate and chemistry.[7; 8]  
 
The world as it was in the late Cretaceous. Image courtesy Andy Gale [1]

All this is wonderful, radical stuff to explore during COVID-19 lock-down. Like astronomy, geology has the power to frame human life against an almost infinite scale of time and space. Like pedunculate cirripedes, we cling for a few seasons to our floating attachment points and then - like them - our debris will inevitably find its way to the metaphorical sea floor. Perhaps only our names, inscriptions and genetic coding will survive us, for a century or two at most. The history of taxonomic revision makes clear that not even species names backed up with diligent taxonomic description may be proof against time. 






REFERENCES

[1] - Gale, A.S. New thoracican cirripedes (Crustacea) from the Cretaceous of Europe and North Africa. Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen Band 295 Heft 3 (2020), pp.243-282. [Link accessed May 2020]
[2] - Southward, AJ. Barnacle Biology. CRC Press, 1987; chapters 2.1 and 2.2.
[3] - Darwin, CR. A monograph on the fossil Lepadidæ, or pedunculated cirripedes of Great Britain. Palæontographical Society, London, 1851 Plate 3, Fig.1. Downloadable here. [Link accessed May 2020]
[4] - Rawson, PF. Cretaceous: Sea Levels peak as the North Atlantic Opens, in: Brenchley, PJ & Rawson, PF (eds). The Geology of England and Wales. The Geological Society, 2006; 2nd Edition. 
[5] - Lee, JR, et al (eds). British Regional Geology. East Anglia. British Geological Survey, Fifth Edition, 2015.
[6] - Csiki-Sava, Z et al. Island life in the Cretaceous - faunal composition, biogeography, evolution, and extinction of land-living vertebrates on the Late Cretaceous European archipelago. Zookeys, no.469, January 2015, pp.1-161. [Link accessed May 2020]
[7] - Jarvis, I, et al. Late Cretaceous (Campanian) carbon isotope events, sea-level change and correlation of the Tethyan and Boreal realms. Palaeogeography, Palaeoclimatology, Palaeoecology, no.188, 2002, pp.215-248.
[8] - Skelton, PF et al (eds). The Cretaceous World. The Open University / Cambridge University Press, 2003.

THANKS TO
  • Andy Gale, for naming the extinct beastie.
  • Gilbert Addison, for suggesting the title of this article.

Saturday, 4 April 2020

A Blackthorn Spring

Cold winds easterly have been blowing across East Anglia for the past week, though temperatures are set to rise this weekend.  Blackthorn blossoms are flourishing in this 'blackthorn spring': their froth of cold, white flowers starting out of the rattling, winter blackness of branch and twig.



Prunus spinosa, is respected by country dwellers for its fruit (sloe gin), its hard, durable wood and particularly for its long, piercing thorns like stiletti. They are able to pass straight through clothing, gloves and even boot soles and car tyres - things I know from experience.

I now have a terrible story to relate. It was told me by my friend C. and began about a month ago when her boyfriend D. was working in a Suffolk wood. Blackthorns make bristling thickets that require careful handling. Even though he was wearing goggles, a chance branch whipped his forehead and embedded a spine in his brow down to the bone. Naturally he pulled it out, but that evening redness and swelling set in, followed later by deep inflammation. Over the following days his condition worsened as his head swelled up and he became very unwell, with symptoms similar to sepsis (blood poisoning). Luckily neighbours noticed his silent home and telephoned C. She drove over immediately and what she found appalled her; a man in delirium, shivering with fever, with a necrotic lesion on his forehead. He was taken to hospital by ambulance and given intensive care. Over the next few days the hallucinations faded - at one time he said he thought his bed was surrounded by tall trees - and his temperature subsided. It was evident that he would need a skin graft to repair the damage, but this would have to be delayed because the hospital had started dealing with a flood of Coronavirus casualties. That is the situation now: D. is waiting and convalescing, wearing a head bandage and lucky to be alive.



What is it about blackthorn that makes it wound so grievously?

A look through my bookshelf did not turn up much useful information.
"A scratch from the thorns would cause blood poisoning. This was thought to be because Christ's crown of thorns was made from it".(1)
"Long associated with dark forces".(2) 
"Other tannin-rich barks were also used [for making inks] particularly those of blackthorn ...".(3)
A trawl through the WWW was more promising.
"On Tuesday evening I was scratched on the hand by a blackthorn, not deeply, but enough to draw blood. Fortunately, I know about blackthorn poisoning: it can be very unpleasant. A piece of blackthorn burying itself under the skin might cause severe infection, blood poisoning, swelling and pain. If left too long before treatment, amputation might be the result. Blackthorns are covered in unpleasant bacteria. If you have a piece buried in your flesh, the best course of action is to get yourself off to the hospital if you have a rapidly escalating and unpleasant reaction; don’t leave it until the area around the wound turns black. My light scratch was reacting badly to the blackthorn toxins within 5 minutes. I sprayed the area liberally with surgical spirits on my return home, which quickly reduced the angry redness and swelling. I woke in night with the swelling raging ... ".(4) 
A comment was appended to this blog post: "Our friend has just died from black thorn poisoning. Thought it was flu …".(5)
"Years ago I ignored a blackthorn wound. Within a week I had a red line running from the inside of my wrist to my elbow warning of the onset of sepsis".(6) 
"Blackthorn injury can give rise to a wide variety of manifestations ranging from mechanical dermatitis, cellulitis, abscess, foreign body granuloma, peritendinitis, tendinitis, pericapsulitis, synovitis to acute septic arthritis. Human synovial tissue is very prone to react to organic substances like blackthorns. Removal of the blackthorn fragments causes prompt resolution of the inflammation".(7)

It is clear that blackthorn wounds can be dangerous, particularly if remnants of thorn are left in the wound. I think D.'s injury was down to more than just a bad-luck thorn-prick.
"Why do [blackthorns] cause so much trouble? Clinical research undertaken at Oakham suggests that the painful tissue reaction to blackthorn injury is not caused by infection. In fact, contrary to popular belief among the equine veterinary community, the joint is sterile after a thorn penetration. The substances that make blackthorns black are alkaloids, and this thorn contains more alkaloids than other plants. Our research indicates it is this that causes the severe tissue reactions".(8)
The website 'Botanical Online' in its 'Blackthorn Toxicity' page states that the toxic principles of blackthorn are: prussic acid (seeds, bark, leaves); hydrogen cyanide (seeds); tannins. Anecdotal evidence from online discussion forums suggests that the blackthorn is particularly poisonous during the growing season.



So, I suggest that what makes a blackthorn wound so grievous is that the bark and thorns at this time of the year are exuding small quantities of plant toxins known as cyanogenic glycosides, notably hydrocyanic acid (HCN, aka prussic acid), "one of the most toxic of all plant compounds. ... The occurrence of cyanogenic glycosides is widespread. Amygdalin and prunasin are very common among plants of the Rosaceae, particularly the Prunus genus".(9) Oakham Veterinary Hospital is probably wrong about alkaloid poisoning: the blackness is caused by tannins, and the toxicity is caused by HCN. The presence of other pathogens such as bacteria from bird muck may play a secondary role, although I imagine most humans and other animals have a measure of immunity against them.

HCN has been tested as a chemical weapon to be absorbed through the skin. According to a Wikipedia, a concentration of 2000 ppm will kill a human in about one minute. "The toxicity is caused by the cyanide ion, which halts cellular respiration by acting as a non-competitive inhibitor for an enzyme in mitochondria called cytochrome c oxidase".  Basically, it kills cells. No wonder D. suffered toxic shock and now has a necrotic lesion on his head.

According to the University of Maryland, "All 400-plus Prunus species are toxic to livestock. ... The most commonly recognized species are the stone fruits: cherries, peaches, plums, almonds, apricots, and nectarines. All parts of the plant are toxic except the mature fruits. ... Hydrogen cyanide acts as a poison by preventing red blood cells from releasing oxygen".(10)

I think I now understand how D. came to be so badly affected by a single puncture wound. Fragments of thorn are likely to have released HCN which led to localised cell death, followed by toxic shock from sepsis and a dermal necrosis. His immune system struggled to cope with the chemical arsenal of Prunus spinosa, and also probably the effects of some bacteria and algal detritus.

I think it would be worth somebody researching more about HCN in blackthorn For instance, I'd like to know whether it is the live or dead thorns that do the most damage. The results would be worth publicising for farmers, gardeners and any other outdoors people likely to encounter this baleful, though attractive and interesting, bush. 




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SOURCES

(1) - R. Vickery (ed.). 'Unlucky Plants - a folklore survey'. Folklore Society, 1985.
(2) - Tess Darwin. 'The Scots Herbal'. Mercat Press, 1996.
(3)  - Richard Mabey. 'Plants with a Purpose'. Collins, 1977.
(4)  - Michael Griffiths. 'Blackthorn Poisoning. A warning'. The Wilden Marsh Blog, 3-12-2015.
(5) - Ibid, comment from 'Debra', April 17, 2018.
(6) John Shelley. 'Nature. A Thorny Issue'. The Mayo News, 1 April, 2014.
(7) - H Sharma & AD Meredith: 'Blackthorn injury: a report of three interesting cases'. Emergency Medical Journal, vol.21, no.3, April 2004.
(8) - Oakham Veterinary Hospital, online: 'Blackthorn injury in hunters / sport horses'.
(9) - Andrew Pengelly. 'The Constituents of Medicinal Plants'. Allen & Unwin, 2009; pp.44-45.
(10) - Sara BhaduriHauck. 'Toxic Plant Profile: Prunus Species'. University of Maryland Extension, 3-8-2015.

All online sources accessed April 2020.

Text and pictures © TD Holt-Wilson, April 4th 2020.