Tuesday 30 June 2020

British & Irish Botany: Vol 2 Issue 2 out now!

Rare Spring Sedge
Image: Pete Stroh
The latest issue of British & Irish Botany has just been published. It's our first issue since we entered lockdown (the last issue was published in February), which has made it impossible for botanists to travel very far from their home patch. So many of the wonderful field meetings and workshops we had planned for you this year have had to be cancelled or postponed! 

But with this latest issue of BSBI's Open Access, online scientific journal, you will be able to travel virtually to locations such as the Scottish Highlands, the Sefton coast in northwest England, the chalk grasslands of southern and eastern England, to South Tipperary (yes it is a long way there...) and as far afield as Fair Isle! 

Read on to find out about the seven papers in our June issue.

First up we have BSBI Head of Science Dr Kevin Walker and England Officer Pete Stroh telling us about changes in the distribution and abundance of Rare Spring Sedge Carex ericetorum. 

Lathyrus latifolius spreading on
the Ainsdale dunes
Image: Phil Smith
If you don't know this rare sedge (yep, there's a clue in the name!) then check out the Species Account on the BSBI website and take a look at the latest BSBI distribution map for the species. 

Phil Smith whisks us away to the Sefton coast to consider the non-native taxa occurring in the coastal sand-dune system. Some of those aliens are showing invasive characteristics: Phil talks us through what those species are, what proportion of the local flora they represent and whereabouts in the dune system they are causing problems. Phil also calls for further studies so that strategies for effective control can be formulated and enacted. 

Stuckenia x suecica growing in the river at
Camus Bridge on the River Suir, Co. Tipperary
Image: Rosaleen Fitzgerald
Chris Preston and Rosaleen Fitzgerald report on an extensive newly-discovered population of a hybrid pondweed from a 60km stretch of the River Suir in South Tipperary. Stuckenia x suecica is the hybrid between slender-leaved pondweed and fennel pondweed but here in Ireland, as in Yorkshire where the hybrid is also recorded, slender-leaved pondweed (the rarer of the two parents) is out of range. Chris and Rosaleen unpick the mystery in their paper.

Nick Riddiford et al. tell us about the wild and naturalised flowers recorded on Fair Isle, including an impressive list of eyebrights Euphrasia spp.. Chris Metherell, co-author of the BSBI Handbook on eyebrights, is also a co-author on this paper. Take a moment to enjoy images of some of the gorgeous eyebrights recorded on Fair Isle and, thanks to Chris, identified with confidence: 

Selection of Euphrasia species on Fair Isle
Image: Tony Vials
We also feature three papers about hawkweeds in this issue. Interest in this challenging genus is high at the moment thanks to the new BSBI Handbook, the 20th in the series: Mike Shaw's  Hawkweeds of southeast England. I have to admit here that as a humble Comms Officer and Editorial Assistant on British & Irish Botany I've managed to avoid hawkweeds so far - there's a good reason for their reputation as one of the most difficult genera in the British flora! So I'll hand over here to my esteemed colleague Dr Ian Denholm, Editor-in-Chief of British & Irish Botany, to tell us more about these three new papers and why we should all learn to love hawkweeds: 

Drummond's Hawkweed at possibly
the only location in the world
where it still occurs.
Image: Tim Rich
"The first of Tim Rich’s two papers as sole author explores the current status of Drummond’s Hawkweed Hieracium drummondii, a rarity only ever recorded from a handful of locations in Scotland. Alarmingly, searches of these sites turned up just one extant colony in Kintyre. Since this species is endemic to Scotland, it is now in severe danger of global extinction. Tim’s second paper uses a combination of morphometrics and field work to demonstrate that previous records from Britain of a different Hieracium species, H. lanceolatum, are erroneous, exemplifying the difficulties of resolving the status and distribution of taxa distinguished by only slight differences in morphology. A third paper produced by Tim with colleagues from the Czech Republic uses a powerful tool called flow cytometry to investigate levels of ploidy and the genetic origins of species in two sections of the Hieracium genus. Instead of detecting difference in DNA sequences, flow cytometry measures the total amount of DNA present in cells and is a rapid alternative to the time-consuming and technically-challenging (and increasingly unfashionable) approach of observing and counting chromosomes directly". 

So there you have our first locked-down issue of British & Irish Botany which takes us not only to locations across England, Ireland, Scotland and Fair Isle but even to laboratories in the Czech Republic. And all without leaving the safety of our homes. If the recent months have left you with time on your hands to write up a recent botanical discovery, we'd love to hear from you. You can either submit a paper for consideration by Ian here or drop him an email to bib@bsbi.org - he'll be happy to talk through your proposal. 

Monday 29 June 2020

Wildflower of the Month: June: Bee orchid

Bee orchid at Monk's Wood, Cambs.
Image: Kevin Walker
In recent months Dr Kevin Walker, BSBI Head of Science, has been focusing on a different wild flower each month. In March it was purple saxifrage, in April it was snake's-head fritillary, May's Wildflower of the Month was meadow saxifrage, and now Kevin focuses on a plant we usually think of as blooming in June on calcareous grasslands in the south. Except that's no longer the whole story... 

Read on to find out what Kevin has discovered about one of our most popular and iconic orchids! 

"Orchids are our most glamorous wildflowers. They are an entry point for generations of botanists and even pique the attention of birders when the flow of spring migrants dwindles to a slow trickle in late May. Their exquisite beauty, complex sex lives and often extreme rarity gives them an allure that is hard to resist and can lead to life-long obsessions. As BSBI member Leif Bersweden captures so beautifully in The Orchid Hunter, it was the discovery of a Bee Orchid as a boy that got him hooked. Leif is in good company. Charles Darwin devoted much of his later life to the “various contrivances by which British and foreign orchids are fertilised by insects” – a book with superb descriptions and line drawings of the fascinating sex lives of many British species.

What's the collective noun for bee orchids:
a swarm?
Image: Rebecca Wheeler
"June is the premier month for orchid hunting. Many of our c50 species flower in quick succession and, if you are lucky enough to know where to look, there are well trodden paths to all but the very rarest species. Wisely, the hallowed locations of the likes of Lady’s-slipper, Red Helleborine and the ethereal Ghost Orchid remain under wraps. The most talked about orchid of them all is the Bee Orchid Ophrys apifera. This colourful mimic, with its bee-like flowers, is one of our most widespread orchids and increasingly the one you are most likely to find closest to home.

"Historically its beautiful blooms were to be searched for in chalk downland, coastal dunes and damp meadows and pastures. But today it is as likely to be encountered on urban road verges and waste ground, or as a colonist of quarries and gravel pits in the early years of succession to more stable grassland and scrub. If you live in England and have never seen one then ask around. Most botanists will know where to find one.

Bee orchids in a sward
Image: Richard Bate
"The fortunes of the Bee Orchid are worthy of a book in itself. It appears to be on the move both ecologically and geographically and these changes are providing tantalising insights into how our environment is changing; if these early indications are correct, it may well be the ‘canary in the cage’ when it comes to climate change and plant conservation.

Close to home…
"One of the wildlife highlights of these long lockdown months has been the abundance of wildflowers in urban areas where councils have relaxed their mowing regimes. This, combined with Plantlife’s #NoMowMay campaign, has led to a surge in records of Bee Orchid. Since it was first reported in flower on the 15th of May by Dr Richard Bate, Twitter has been alive with records, many from garden lawns: participants in the BSBI’s Garden Wildflower Hunt have been sending us records of bee orchid sightings in their gardens and telling us how delighted they were to welcome these visitors!

"My nearest colony is about fifty metres from my front door. I’ve been keeping a close eye on this little colony and these observations have been very revealing. The first thing to note is that it is flourishing on a very ordinary roadside verge which can only be described as a billiard table. Most of the plants rarely, if ever, get a chance to flower; those that do have to endure football games and mowers and this year a severe frost in late April followed by a month-long drought in May. Many blackened off and died back. A few have flowered probably a week earlier than normal. Flowers first appeared on “my” bee orchids on the 2nd of June. In normal years (whatever that now means!), they are usually at their peak between 9th to 24th June. Anecdotally botanists tell me that it was never worth looking for their flowers before mid-June.

A meadow full of bee orchids and other
native wildflowers
Image: Rebecca Wheeler
"What’s also revealing about “my” colony is its location. It’s not particularly special – just some grass strips in a modern housing estate built on a former MoD site in the 1990s. The grassland, which is not totally devoid of interest (Knotted Clover Trifolium striatum grows with the bee orchids), could have survived the construction work or was possibly seeded afresh, creating ideal conditions for Bee Orchid – which likes bare ground - to colonise.

"So it is not surprising that we are getting lots of reports of Bee Orchids in garden lawns. This reminds me of another orchid that made a spectacular appearance in gardens after the scorching summer of 1957. Severe drought meant that many lawns were left uncut and this led to flurry of reports of Autumn Ladies-tresses Spiranthes spiralis from gardens, so much so that it was reported in The Times. This mass seeding event lead to a dramatic increase in populations in subsequent decades, so perhaps an unintended consequence of this lockdown will be a similar increase in Bee Orchid colonies in years to come?

Spreading north…
Graph showing northward spread of
bee orchid over time
Graph by Kevin Walker
"Scientists have shown, unequivocally, that some butterflies, dragonflies and birds are expanding their ranges northwards as climate change opens up new areas of habitat to them. Evidence for plants is much harder to come by: maybe that’s not that surprising. Wildflowers are by nature sedentary; they don’t move much and if they do, their dispersal is measured in metres rather than kilometres. The main exceptions are orchids. Each flower produces thousands of dust-like seeds and these can be dispersed over large distances by air currents. It has even been suggested that the North American orchid known as Irish Lady’s-tresses Spiranthes romanzoffiana, a rare plant of the western seaboard of Britain and Ireland, might have been blown across the Atlantic during gales. The attractive Mediterranean tongue orchid Serapias lingua appeared in Essex a few years ago and again wind dispersal has been mooted as the means by which it arrived on our shores. In both cases there are other theories but the most parsimonious would seem to be wind. 

Bee orchid
Image: Richard Bate
"Of all the British orchids, Bee Orchid has shown the most spectacular increase in recent decades. Back in the 1960s, it was largely confined to grassland in southern and south-eastern England with odd records stretching as far north as County Durham. Since then it has been gradually extending its range northwards (see the graph above) especially in northeast England where it has spread along the coast. It was first recorded in Scotland in 2003 and now occurs as far north as Glasgow and Edinburgh, and I’m sure it will spread further, probably in sandy grassland along eastern and western coastlines, in the not too distant future.

"As intimated above it also appears to be broadening its ecology. In the first edition of Clapham, Tutin and Warburg’s Flora of the British Isles, published in 1952, its habitats were described as “pastures, field-borders, banks and copses on chalk or limestone, especially on recently disturbed soils; also on base-rich clays and calcareous dunes.” Today you are as likely to see it off calcareous soils as on them, on roadside verges, spoil heaps, urban waste ground, disturbed soils in old quarries and gravel pits and abandoned farmland.

Seeds of its success…
Bee orchid close-up
Image: Richard Bate
"So what is the secret of the Bee Orchid’s success when so many other wildflowers have declined? Despite its bee-like appearance, self-fertilisation appears to be the norm rather than deception to entice cross-pollination by bees (as in other Ophrys species). Unlike some other orchids, individuals can continue to flower for a number of years. As a consequence, populations are likely to grow very quickly. This coupled with its ability to spread its seed far and wide means that it can quickly colonise new habitats as they come within reach.

"Like most plants, orchids face a trade-off when it comes to seed size. Dust-like seeds are great for getting around but do not have enough food to support the growing embryo once they land. Many orchids strike a deal with soil mycorrhizae gaining nutrients from the fungus as they grow. But this is the Achilles heel of many orchids species and the reason they are so rare; highly specialised relationships severely restrict where they can grow. We can only assume that the Bee Orchid has chosen a range of very widespread and common fungi with which to share its food.

Bee orchid rosette with 20p coin
standing in for a scale bar
Image: Kevin Walker
"But possibly at the root of its success has been its ability to adapt to rising temperatures in recent decades. Bee Orchids are wintergreen; in fact, winter is the easiest time to spot their distinctive rosettes. Many participants in BSBI’s New Year Plant Hunt spot the rosettes while they are out looking for wild plants blooming in midwinter. Mike Waller’s Beginner’s Vegetative Guide to Orchids of the British Isles is very helpful for anyone who isn’t sure what to look for. As our winters have become less severe, Bee Orchids have clearly benefited especially in urban and coastal areas, where severe frosts are less common.

"We humans have accentuated these trends by creating the disturbed, early successional conditions that they seem to love. Since the 1950s we have transformed our lowland landscapes through a massive expansion in road and rail networks, industrial land, waste ground, restored colliery and landfill, and abandoned quarries and gravel pits. Bee Orchids have benefited from these transformations.

"So the Bee Orchid is probably the nearest wildflower we have to a ‘canary in the cage’; its fortunes tell us much about how our climate and landscapes are changing. But more than that, this adaptable little orchid continues to enthrall and excite us; as the celebrated and much-loved illustrator Cicely Mary Barker observed in her ‘Song of the bee orchis fairy’, a day when you discover a Bee Orchid is always 'your luckiest day'!” 

Tuesday 23 June 2020

A virtual walk through the trees...

Fal with her poster at the
2019 BSBI Exhibition Meeting
One of the popular flash talks and posters from last year's BSBI Exhibition Meeting was from Fal (short for Falgunee) Sarker who told us about 'An experience of nature for the visually impaired'. This was a local pilot project, funded by the Heritage Lottery Fund and formulated by the Tees Valley Wildlife Trust, to help connect visually impaired people with nature. 

Fal led a series of walks in South Park, Darlington between August 2019 and March 2020 and another walk was planned for May this year but then... well you all know what happened to prevent public events going ahead! 

Undaunted, Fal responded to the lockdown by "taking the visually impaired friends with a virtual walk through trees after trees. At this time of self isolation, this is one of the ways to
bring some joy, by recalling the memory of their walk together".

Last autumn's walk for the visually impaired.
South Park, Darlington
Fal says that South Park, Darlington, where the original walks took place, has "many old trees, wild flowers, wild sensory garden and a lake. We offered the visually impaired friends a guided walk with one to one support. Trees and wild flowers offered texture, smell, sensory stimulation with leaves, seeds, cones, wild flowers with unique perfume, also the mosses were sensational. Blind people could not have experienced that without the help of this project". 

Fal's script for this spring's virtual talk recreated the experience of the actual walk by leading the visually impaired friends through memories of what they had enjoyed a few months before. Starting at the gate of the park, she described the trees they had experienced, reminding them of the "crispy bracts" of the hornbeam and the criss-cross bark and soft leaf of the tulip tree; of the scent of the roses in the Rose Garden; of the sound of the water in the adjacent River Skern; the scent and feel of the pine needles, the bark and cones of the Atlas cedar and the Wellingtonia in the conifer woodland.

The walks for the visually impaired are a lovely idea and I think Fal and her colleagues should be congratulated for being so resourceful - they didn't want the friends to miss out on their springtime walk due to the Coronavirus, so Fal took them on a virtual walk instead!

Sunday 14 June 2020

Flora of Cornwall: coming soon

There's a new county Flora in the pipeline and it will be on sale soon for an RRP of £50 but you can save £10 if you order your copy now.

The Flora of Cornwall by Colin French, BSBI's County Recorder for West Cornwall, is a 550-page, full colour, hardback book. It covers 3,018 flowering plants and ferns and includes over 1200 distribution maps and more than 1,700 photographs. There are sections on the effects of climate, geology, soils, topography, mining, quarrying and agriculture and there is also information on vegetation history, key habitats, botanical regions, recording history, losses and gains, and rare and/or threatened plants. 

You can order your copy now by contacting Colin at whealagar4@gmail.com. Now read on as Colin tells us about the book, the plants and the county:

"Since 2007, a small group of dedicated volunteers has systematically surveyed Cornwall's wild flowers, visiting as many habitats as possible in every single one of Cornwall's 3,940 one kilometre squares. The result is the most comprehensive and intensive survey ever undertaken in Britain: more than 1.4 million wild flower sightings were gathered and digitised (more than has been collected for the whole of Scotland in that period!), increasing the total number of plant records for Cornwall to 2.25 million.

"Cornwall is a special place which attracts legions of visitors from Easter to September who come to experience an exotic land with spectacular unspoilt scenery. It is a land where the place names belong to a different language, with its own culture and traditions. A land where the Cornish have fashioned a unique rural countryside with sizeable expanses of semi-natural moorland and heathland, enmeshed by a cloth of Cornish Hedges and open treeless vistas. A frequent cry is how lucky we are to have so much wildlife habitat and such a rich and diverse environment to live in. 

"Sadly such first impressions are deceiving. This ‘unspoilt’ land has been inexorably declining for decades both in the amount of wildlife habitat available and overall biodiversity. By analysing the data collected during this survey and comparing it with historic records, we found that, while no native plants are known to have become extinct in Cornwall since 1982 - in stark contrast to many other parts of Britain - at least half of Cornish natives and archaeophytes were more widespread before 2000 and a minimum of 40% of Cornwall has lost 90% of its flora in the last 50 years. So clearly, Cornwall has not been immune from the immense changes that have been badly degrading the biodiversity of the rest of lowland Britain.

"Many exciting discoveries were, however, made in the course of the survey work for the Flora of Cornwall (sample pages above and below). In total 426 plants were added to the Cornish tally - mostly alien plants/ garden escapes, some of which are new to Britain as wild plants, such as Hook Sedge Carex uncinata which originates in New Zealand. 

"Even more exciting was the discovery of two plants which were new to science: 
  • A hybrid willowherb between New Zealand Willowherb Epilobium brunnescens and Small-flowered Hairy Willowherb E. parviflorum
  • A hybrid between Fragrant Orchid Gymnadenia borealis and Southern Marsh-orchid Dactylorhiza praetermissa which was discovered, new to science, on the Lizard Peninsula in 2016. (Image on right).
"A number of native plants were also found in Cornwall for the first time, including:
  • Service-tree Sorbus domestica - one of Britain’s rarest native trees. A single tree was discovered on the bank of the Camel Estuary in 2013.  
  • Bog-sedge Carex limosa was found on Bodmin Moor in 2017. The nearest Bog-sedge colony to Bodmin Moor is Crymlyn Bog, Swansea. This very rare sedge is classified as being endangered of becoming extinct.
  • Diaphanous Bladder-fern Cystopteris diaphana was discovered as new to Britain in 2000. Before this all the Cystopteris fern plants in Cornwall were thought to be Brittle Bladder-fern C. fragilis. It was then realised that the Cornish plants were a different species, which was previously unknown in Britain.
  • Inland Club-rush Bolboschoenus laticarpus was discovered in 2004 at Porth Reservoir. This is another species which went unrecognised in Britain until in 2010 when it was realised that the inland form of Sea Club-rush Bolboschoenus maritimus was a completely different species. Since then this new species has been found at six sites across Cornwall.
  • Sea Daffodil Pancratium maritimum was first noticed in the dunes at Marazion in 2006. It grows in north-west Brittany so seed may have crossed the Channel and reached Mount’s Bay.
  • Perennial Glasswort Sarcocornia perennis appeared at Carnsew Pool, Hayle Estuary in 2012.
  •  Long-spiked Glasswort Salicornia dolichostachya was first noted at Copperhouse Pool, Hayle in 2014. This and Perennial Glasswort may have arrived with wildfowl.
  • A hybrid fern called Polystichum x lesliei was found at Tywardreath in 2001. This is the hybrid between the native Hard Shield-fern Polystichum setiferum and Western Sword-fern P. munitum. This discovery has the distinction of being the first spontaneous hybrid between a naturalised alien and a native fern species ever to be found in the wild in Britain.
  • The hybrid between Wavy St John’s-wort Hypericum undulatum and Square-stemmed St John’s-wort H. tetrapterum was discovered new to Britain in 2006.

"In addition to those important finds, nine plants, which were thought to be extinct in Cornwall have been rediscovered. These are Broad-fruited Cornsalad Valerianella rimosa last seen in 1954; Oak Fern Gymnocarpium dryopteris last reported in 1930; Beech Fern Phegopteris connectilis last recorded in 1930; Dense-flowered Fumitory Fumaria densifora last seen in 1921; Corn Buttercup Ranunculus arvensis - the first record since 1974; Stag’s-horn Clubmoss Lycopodium clavatum last reported in 1920; Blunt-flowered Rush Juncus subnodulosus last seen in 1879; Sand Crocus Romulea columnae and Perennial Centaury Centaurium portense (image below left)

"Sand crocus was found growing on the clifftop near Polruan in 1879 and 1881 and despite repeated searches was not seen again until 2002 at another site on the cliffs near Polruan. The only other site for this extremely rare, distant relative of the garden crocus, is at Dawlish Warren, in South Devon. Perennial Centaury was thought to have become extinct in 1962. It was rediscovered at the same site, near Porthgwarra, in 2010, causing much excitement, as the only other British population is in Pembrokeshire.

"Finally - and surprisingly - 63 endemic plant species were found growing in Cornwall, including Cornish Ramping-fumitory Fumaria occidentalis which is only found in Cornwall and the Isles of Scilly, and Logan’s Sea-lavender Limonium loganicum which only grows near Logan’s Rock, near Porthgwarra".

Many thanks to Colin for telling us about the new Flora of Cornwall. It's obvious that for anyone who lives in or visits Cornwall and wants to know more about its wild plants, the Flora will be essential, but as the above summary makes clear, it will also make fascinating reading for anyone interested in plant distribution and how our wild plants are changing. So if you wish to order a copy of the Flora of Cornwall and save £10 compared to the RRP of £50, please contact Colin now at whealagar4@gmail.com.

Sunday 7 June 2020

Trevor James 1947-2020

Trevor (in green) enjoying a drink with colleagues
Paul O'Hara, Arthur Chater and Chris Boon after
a meeting of BSBI Publications Committee
Image: L. Marsh
We are very sorry to report that Trevor James, former editor of BSBI News, BSBI joint County Recorder for Hertfordshire, longstanding member of BSBI Publications Committee and a leading figure in British biological recording, has died. 

Trevor was awarded a British Empire Medal in this year's New Year's Honours List in recognition of his services to nature conservation.

An obituary will follow in due course but for now, this tribute from Hertfordshire Natural History Society outlines some of Trevor's many achievements. 

We'd like to extend condolences to Trevor's family and all his many friends and colleagues at this very sad time. He will be greatly missed.