All posts by Chris Gibson

Murder at the Garden Pond: Thalia dealbata – the (not very) beautiful assassin

Beth Chatto Gardens, Britain's Wildlife, WildWivenhoe

‘An evergreen, marginal aquatic perennial forming a clump of long-stalked, erect, narrowly ovate leaves to 40cm in length, covered with white powder, and slender stems bearing panicles of purple flowers 2cm across’. This, from the Royal Horticultural Society, neatly sums up the rather statuesque plant that we encountered in Beth Chatto’s garden last summer: Thalia dealbata.

As per usual, when in gardens we seek out insects to photograph and were immediately aware that this plant was covered in SO many pollinators. But dead pollinators. On closer examination, each flowerhead was actually riddled with corpses – hoverflies, lacewings, bees, wasps and blow flies, amongst others – a glistening mortuary for those valuable garden assistants, pollinators and predators alike, all stuck headfirst into the mouths of their nemesis.

The scale of the carnage was, quite simply, shocking. Some, still alive, like this Honeybee we managed to release, but most were dead. Lost to the world.

Reference to the internet shows this is a recognised phenomenon. The plant has no reason to kill its visitors – it doesn’t digest them like a truly carnivorous species: it seems that the flowers have an elastic style, used in explosive pollination which can and does trap insects.

In its native central American/southeastern USA range it is normally pollinated by large and powerful Carpenter Bees, capable of extricating themselves from the flower’s fatal embrace. Anything smaller is trapped and starves, mere collateral damage, cannon fodder in the battle for life.

 

But at times of an Extinction Crisis, that is one pressure our array of pollinators, necessary not just for the plant’s but for our species’ continued existence, can do without, dozens of pollinator lives being extinguished unnecessarily for each flowerhead. We raised our concerns with the Beth Chatto gardeners, and they promised to investigate, perhaps to remove the spikes of (to our eyes, rather unlovely – they often don’t seem to open fully) flowers, leaving only the stately leaves to give emergent architecture to the water margins.

And to their credit, the Beth Chatto online sales catalogue does at least draw attention to this antisocial behaviour attribute of Thalia: ‘Please note that the plant has an unusual mechanism for pollination which results in some pollinating insects remaining trapped within the flower, where they can perish. Hover flies appear the most affected.’

No other suppliers that we came across made any such references to the ‘special properties’ of Thalia, so we started a bit of a Twitter campaign to raise awareness, and perhaps get restrictions on the sale of the species, or to at least persuade suppliers to inform potential customers of the plant’s fatal attraction. And perhaps in response to this, we note that six months on, the RHS website now contains the following sentence: ‘Although not carniverous [sic] as such, this plant may trap and kill small insects such as hoverflies and small bees during the pollination process.’ Not the unequivocal recommendation not to buy and grow it that we might have hoped for, but a start nonetheless…

The RHS also provides a list of recommended stockists, of which six are noted for Thalia, one in France and five in the UK (including Beth Chatto’s). Two of those seem no longer to list it on their catalogues, but that still leaves three well-known British aquatic plant suppliers who do without hesitation, one even noting it is ‘much frequented by butterflies, moths and other pollinators’ without giving the full story. And of course other UK suppliers are available, though in the first three pages of a Google search, none referred to Thalia’s nasty little habits, save for World of Water Aquatic Centres which in its information table asks ‘Perfect for Pollinators?’, and gives the answer ‘No’, albeit without explanation.

We shall be contacting suppliers to try and persuade them to at least mention this issue, if not withdraw it from sale , in the hope that insects can be saved and eco-conscious gardeners are not upset at the behaviour of their latest purchase. And future updates to this blog may include a ‘name and shame’ as well as a ‘Hall of Fame’!

 

IMPORTANT UPDATE AUGUST 2020

It is with great pleasure I can report that the staff and management of Beth Chatto’s have responded very positively to the issues raised by Thalia, and this summer initiated a regime of removal of the flowering spikes as they start to emerge. Their actions and thinking is detailed in a recent blog  by Dave Ward: see here.

They may still be selling the plant, but only with a strong advisory note to buyers to follow suit and ensure flowers are removed. Let’s hope that other gardens, nurseries, suppliers and industry bodies will take note, and do likewise.

#WildWivenhoe Botany & Bug Walks: February awayday to the Naze

Britain's Wildlife, Bug & Botany Walks, WildWivenhoe

What could be better – a walk on the beach on a sunny afternoon, time to scrabble about and get dirty hands in the search for fossils and other beach treasures, followed by tea, cake and chat in the warm?  Our intrepid Bug-and-Botanists all had a whale of a time on Saturday at The Naze, and despite there being a distinct lack of botany (except of course Gorse) or bugs to admire, there was plenty of ‘nature’ to enjoy!

Standing on the beach looking at the cliffs, you really are looking back many millions of years in time.  The whole area, a Site of Special Scientific Interest, is one of the finest geological sites in Britain, comprising layers of London Clay, topped by Red Crag.

The stunning redness of the Crag is due to oxidisation of the sand and fossil layer laid down over 3 million years ago when Walton was, as now, at the edge of the sea, just prior it being engulfed in the turmoil of the last Ice Age. Fossils of many kinds and shell debris can be readily be found on the beach, most stained an attractive red colour, distinguishing them from otherwise-identical modern shells.

A combination of the seeping of rainwater downwards, lubricating the clay surface, and storm wave pressures makes the whole area prone to landslips and substantial coastal erosion, which although a delight for geologists and fossil-hunters, nevertheless is extremely worrying for those with buildings atop the cliffs!  One example of course is the famous Naze Tower, a 300 year old landmark, built by Trinity House for navigational purposes and which today is a popular art-gallery and tea room.  Some years ago a local dispute raged as to what to do – completely surround the whole Naze with a sea defence?  (extremely expensive and would prevent geological discovery and the ‘production’ of sand which feeds our local seaside resorts), or let the whole area eventually fall into the sea?.  A compromise was sought and about ten years ago an additional 170 metres of defence was built.

Now known as the Crag Walk, this allows a safe walkway, and provides a chance to study the cliffs at close quarters, whilst learning about the geology and wildlife from interpretation boards. It also protects the area immediately below the tower.

And so to our beachcombing….many delights awaited the patient explorer, but sadly no 50 million year old shark’s teeth,  from inhabitants of the subtropical London Clay lagoon which then covered most of what is now Essex, were forthcoming this time.  Our photo shows one that ‘we found earlier’ on a previous visit….

‘Boring piddocks’ Chris was heard to exclaim at one point….to whom or what was he referring?  Turns out Piddocks, also known as Angels’ wings, are attractive shells which bore vertically in the soft London Clay, making perfectly round holes as they do so.  These examples (above left) are modern, as is their holey now-deserted home in the right hand image. Other delights in this photo include ancient pyritised wood (turned to ironstone), and fossilised poo known as ‘coprolite’. Fifty million years old!

The ubiquitous left-hand coiling whelks Neptunia contraria are interesting as most gastropods coil in a dextral way;  these left-handers from the Red Crag seas can be dated at over two million year old.  It’s hard to get your head round numbers like this!

Although quite slippery on the London Clay platform, areas of sand became more accessible as the tide receded and we were particularly struck by the beautiful dendritic drainage tree-shapes in the sand.  So  much to see, but the time came to leave the beach and we finished our session with a cliff-top walk, admiring features on the skyline, and taking the opportunity for some wildlife-spotting:- a Common Seal bobbing along, Brent Geese feeding and a perfect chance to see a beautiful male Sparrowhawk at rest on the Crag.

We look forward to kicking off our season of Botany and Bug Walks proper in April, and hope that some of you will be able to join us.

Beth Chatto Gardens – sunlight and shadows

Beth Chatto Gardens, Britain's Wildlife, WildWivenhoe

The winter thus far remains stubbornly at arm’s length, save for a few frost-washed mornings. The crisp blue light of a midwinter morn has been hard to come by too, temperatures held up and spirits lowered by seemingly unremitting gloom.

But at last today the skies cleared and the garden once again came into its own.

Sunlight and shadows….

Seedheads and sprinkles…

Subtle splendours…

And scentwaves and snowdrops.

 

Beth Chatto Gardens: the reawakening of the year

Beth Chatto Gardens, Britain's Wildlife, WildWivenhoe

‘Reawakening of the year’ hardly seems appropriate, as hitherto the winter slumber has been barely discernable, with few frosts, and bees and other insects around us all the time. As worryingly now seems to be the norm.

Maybe ‘renewal’ is a better term: last year’s leafy growth is playing its final role as a blanket protecting the coming seasons’ primordia from environmental extremes, before breaking down into the nutrients they need to fulfil their potential…

…while tussocks of grass and other plants again provide shelter for overwintering invertebrates, and sources of food to seed-eaters. In too many gardens – happily not Beth Chattos – these would have been ‘tidied up for the winter’.

New spring greens are already coming through, with added colour from variegations and coloured bark, perhaps more obvious and appreciated at this time when flowers are at a premium.

And likewise now is the time to appreciate the trees for what they are, liberated from the distraction of blowsy flowers all around. Standing for decades, centuries even, like old furniture they are so often ignored, but what a delight they are, hinting at the riches they have already given us and promises for the future.

Structure and texture are best appreciated when the sun shines, and this is when their trunks play a role for the few insects on show, sheltered spots for basking flies, even on a cold day like today.

On a warmer day, no doubt many more insects would have been evident, roused from winter torpor and needing to feed to replenish resources for any cold snaps to come. Herein lies the value of a garden: in January, the countryside is pretty much devoid of pollen and nectar sources apart from Gorse. But in a good garden, the ‘winter nectar gap’ can be closed, an essential feature in these times of climatic disruption.

Moreover, some of those plants have a scent that intoxicates even the most jaded human snout, from spicy Wintersweet to rich Witch-hazel, the delicate lily-of-the-valley fragrance of Mahonia to the ultra-sweet wafts of Sarcococca.

 

Identification by Internet…

Britain's Wildlife, WildWivenhoe

May 2012, we were undertaking a butterfly transect for the national monitoring scheme within and close to the Great Notley Country Park, near Braintree. An unexpected shower at the end of the transect caught us out, but trudging back damply along the rather unprepossessing-looking hedgerow and track between two intensive arable fields, our eyes were drawn to a mating pair of insects….

Or I should say ‘mating pair’: examining our single photo back home revealed a superb example of ‘two becoming one’, the head (even down to the eye-glint) of the ‘one on top’ actually the pattern on the lone insect’s thorax, as if its head had been cloned there with Photoshop.

But what was it? It seemed to be a sawfly, a type of wasp without a wasp-waist, but after flicking through the paltry coverage of that group in available popular field guides, we rapidly drew  a blank. The 500 or so known species of sawfly in the UK are very poorly known, as all but a few of the more easily recognisable ones are omitted from the guides. Such a collective information gap is very unfortunate, especially when you see that many also have distinctively marked and wonderfully charismatic ‘caterpillars’, or distinctive feeding signs and galls. Just a few are shown below:

Anyway back to our ‘mating pair sawfly’. We were busy, and the photo got relegated to a pending file… until 2019 when scrolling through some of the riches of the internet, we saw something that triggered a lightbulb moment of recognition. Once we found our image, there it was – Pamphilius sylvarum. Except that is a species with records from only nine previous localities in Britain, ranging north to the Welsh borders, near Wrexham, and Sherwood Forest. The sole other Essex record came in May 2019 from Chigwell, in the Metropolitan sector of the county, courtesy of Yvonne Couch. As well as its scarcity, the habitat of ours seemed odd, given its assumed reliance on oak leaves (which its larvae roll up), perhaps in a woodland or woodland-edge context. There were several spindly hedge oaks within a few tens of metres of our specimen, but otherwise just a hedgerow and open arable. A more uninspiring location for such a rare insect is hard to imagine.

Nonetheless, we could not find much about it, nor about potential lookalikes, so I posted the picture on Twitter, and within a day, had the collective thumbs up from such experts as Steven Falk, Andy Musgrove and Andrew Green.

This episode brought to mind a similar finding from the Beth Chatto Garden, near Colchester. On one of our regular visits at the very end of October 2016, insects to photograph were few and far between, but we did find a fly sitting in a geranium flower. Once again, close examination of the photos showed it to be something different, and unknown to us. It had the appearance of a blow-fly, but with markings not unlike a hover-fly, and excitingly striped eyes, more like those of a horse-fly.

Once again scrolling through the internet came to the rescue, suggesting it was the Locust Blowfly Stomorhina lunata, an egg predator of locusts and grasshoppers, normally well to the south of the UK. Perhaps reflecting its spatially unpredictable feeding preferences, it is a known wanderer, including to the UK, albeit rarely, although seemingly increasing in recent years. In fact in the previous year there had been the largest known migratory arrival in Britain to date, one of which was in Essex at Rainham, only the second record for our county. The identity of our specimen was then confirmed by Del Smith, the fly recorder for the Essex Field Club.

Of course we cannot assume either of these rarities are actually as rare as the paucity of records might suggest. Quite likely their distribution reflects the distribution of recorders rather than the species, especially given the lack of popular illustrated insect guides which cover such oddities.

The internet and social media are much maligned, with considerable justification, but they can give access to more information about insects of all sorts than we could have imagined a few years ago, at least for those without easy access to a museum collection. But BEWARE! As noted on the British and Irish Sawflies website, ‘The internet is awash with incorrectly identified sawfly images so it is recommended to avoid identification by Google searches. The image galleries on this website and on the links below are sourced from known and trusted hymenopterists‘.

Therein lies the answers. By all means use the available picture resources to attempt an identification, but one should always give greater weight to expertly determined and curated sources. And then use social or other networks to get confirmation. If forthcoming, then importantly the records should be submitted and captured for posterity, ideally via a web portal such as iRecord. As always, there will be some species whose identity cannot be ascertained definitively from a photo. As ‘ethical naturalists’ who don’t wish to kill things in pursuit of our hobby, knowing and accepting our limitations is crucial.

#WildWivenhoe Botany & Bug Walks: January – trees in winter

Britain's Wildlife, Bug & Botany Walks, WildWivenhoe

January’s walks were short and sweet, and concluded our three ‘Tree-mendous’ winter events. We walked around the edges of King George’s Field looking at winter twigs, bark and tree shapes.

Below is a series of close-ups of Chris’ photos of some of the twigs we looked at, with a brief description:

ASH  Twigs straight and slightly flattened below the buds, which are black and distinctive and usually in opposite pairs.

BEECH  Twigs thin and zigzagged.  The buds are long and slender, with a waxy white tip, and spread out from twig at a 60 degree angle.

HORNBEAM Twigs slender and zigzagged.  Buds long and pointed, like Beech, but appressed close to, even curved into, the twigs.

HORSE-CHESTNUT Twigs thick, with horseshoe-shaped leaf scars.  Buds with large red-brown scales, not yet quite at the stage of developing their characteristic stickiness.

SWEET CHESTNUT  Twigs shiny and markedly ridged, with heart-shaped leaf scars, showing numerous vascular bundle scars.  Buds plump, reddish and sit on ‘shelves’.

OAK  Twigs widely branched, showing numerous pale lenticels (‘breathing holes’)  and often decorated with woody galls.  Buds plump, orange-brown, and clustered and scaly.  The number of visible bud scales is diagnostic of type of oak: fewer than 20, as here, indicates Pedunculate Oak.

SYCAMORE  Twigs greyish, often with ‘wrinkled stockings’, the stacked leaf scars from previous years. Buds large and pale green, in opposite pairs, but with a lovely purple edging and a white fringe. See, even dormant buds can be beautiful and exciting! And you really do not need leaves and flowers for identification: botanists should never hibernate!

We are indebted to The Field Studies Council for their very informative booklet ‘Winter Trees, A photographic guide’ for inspiration and information. https://www.field-studies-council.org/shop/publications/winter-trees-a-photographic-guide-to-common-trees-and-shrubs/

 

The Beth Chatto Gardens throughout the Seasons: December – after the election, Nature Cure

Beth Chatto Gardens, Britain's Wildlife, WildWivenhoe

A dismal morning, literally and figuratively.

The streets were empty, humanity subdued.

So to a familiar place of refuge, to immerse myself alone in the nature of the garden.

The foliage and fruits from summer and autumn marked the passage of time with sombre hues.

But life clings on….

…some even erupting into a much-needed sign of hope for the future.

Cockaynes Reserve – landscapes, wildscapes and groundscapes dressed in the fires of autumn

Britain's Wildlife, Cockaynes Reserve, WildWivenhoe

The first frosts of winter arrived a couple of days ago, but winds have been light and so the fiery hues of autumn remain around Cockaynes Reserve for now. From trees to reedbeds, leaves are bronzing as if to intensify the feeble sunlight, although today it wasn’t making much impression on the cool easterly air-flow…

Wildlife was of course hiding away, as often as not in plain sight: almost everything we saw seemed to be painted in the palette of decaying chlorophyll, from all manner of fungi to seeding Reed heads to Feathered Thorn:

And then there were the Groundscapes, the pattern of leaf-shapes and colour beneath each species of tree, as distinctive now as at any time of the year. For me, these unique combinations are the shroud of the passing year: here lies Field Maple, Silver Birch, Ash, Sweet Chestnut, Hornbeam, Oak and Hazel.

#WildWivenhoe Botany & Bug Walks: November – autumn trees and fungi in Wivenhoe Park

Britain's Wildlife, Bug & Botany Walks, WildWivenhoe

The weather forecast was not wonderful, but leading the charmed life that we often seem to do, all remained calm and dry for our foray into fungi and trees this month. We spent two very enjoyable sessions at the University of Essex campus, which despite being on our doorstep is somewhere, incredibly, we have rarely visited.

The park is impressive, comprising a landscape of native and some rather special non-native trees, most planted as features for the grounds of Wivenhoe House, a splendid structure built in the mid-18th century and now a successful hotel. The fungi did rather steal the show, though,  as we discovered a spectacular array of them at every turn (although no longer at their best following the hard frost earlier in the week).

Some particular specimens which caught our eye :

Fly Agaric, everyone’s favourite red and white spotty one

                                   

Puff Balls, puffing away

                 

Beefsteak, so well-named, it made a few of us vegetarians feel quite queasy!

Redlead Roundheads, fairly new to UK and only found on bark chippings

Ink-cap, the gills of which drip a black inky substance, the phenomenon known as ‘deliquescence’

The Seamed Monkey-tail   – we thought this was a new-to-science fungus until we realised it was only the tail of a long-lost, half-buried child’s toy!

Yellow Waxcaps – attractive little fungi

Yellow and Grey Clubs – tiny finger like structures, the Grey species being quite a rarity.

Of course, these walks are advertised as ‘Botany and Bug’ so we did try a bit of bug-hunting too and a few things did present themselves, including, perhaps surprisingly, two species of butterfly, Red Admiral and Speckled Wood, plus a Squash Bug and a few hibernating ladybirds in the odd-looking, but insect-friendly Monkey Puzzle tree. A couple of species of harvestmen and short-palped crane-fly were found basking in the weak sunshine.

But the main attraction of the day was the wonderful trees. Today’s walks were part of our series of arboreally-related winter events.  Next month is our Leaf Identification Workshop, and in January our short walk around KGV looking at winter twigs and bark, both intended to increase our knowledge of trees.  Comparison of some different barks showed that this can be a useful identifying tool for when the trees are leafless.

The English (or Pedunculate) Oak, is a stately and magnificent tree familiar to us all, and several superb examples were seen.  A bit of botanical nomenclature for you – ‘pedunculate’ means their flowers/acorns grow on peduncles or stalks, whilst the leaves have none and grow directly out of their twig.  (Another Oak form the ‘ Sessile’ which actually means ‘non-pedunculate’, has, yes you’ve’ got it, stalkless flowers and acorns, whilst the leaves have a stalk).

Other forms of Oak were also looking good – fantastic Red  and Scarlet species, simply stunning at this time of year before their leaves drop; the giant-leaved Daimyo Oak a non-native found only in a few places; and of course the famous Cork Oaks living near the House itself. Rumour has it that General Rebow brought these two back from the Peninsular Wars, planted up in his spare pair of wellies.  They have enjoyed their time at Wivenhoe since then and are cherished specimens in the grounds.

A trio of Redwoods also are worthy of note. The Giant and Coastal Redwoods in their native North America grow to huge heights, indeed are thought to be the world’s largest trees. The Giant (aka Wellingtonia)’s bark is soft and spongy and makes a cosy home for Treecreepers.  A third species, Dawn Redwood, is a very interesting species.  This deciduous conifer was known only as fossils, until living specimens were discovered in China and introduced to Britain and elsewhere in the 1940s.  A hopeful example of extinction rebellion!

The Cedar of Lebanon could not be missed, being huge and was a popular choice for parks and formal gardens when the House was built, as was the Himalayan Pine.

And so to native species, like Silver Birch,  Beech, Ash, and Wild Cherry, all of which are understated and beautiful in their own right and have the space and location to look their best in somewhere like Wivenhoe Park.

The Horse-chestnut, which we may think of as native is in fact an introduction from the Caucasus,  where rather shockingly it is now on the Red Data list, meaning its scarcity is of extreme concern.  It is planted throughout Europe, but is now subject to attack from the Horse-chestnut Leaf-miner moth Cameraria ohridella which causes the leaves to turn brown prematurely and whilst not actually damaging the tree must compromise the efficiency of the leaves .

We thank those of you who participated and hope that you enjoyed it as much as we did. And very grateful also to Dr James Canton who first introduced us to the University Tree Trail, and shared his unique insights as a ‘wild writer’ with us.

All the above photos are ours but not all were taken on the day. Some were from our recce, so the fungi might be looking a bit fresher than you remember!

For a different, delightful perspective on the walks, the perspective of the participant, you might like to look at Helen Chambers’ own blog ‘Fascinating Fungi‘.

The Swiss Alps by train: joining the 6% club

Overseas Tours - other, Travel by Rail

At the very end of August, we made our first trip to Switzerland, and had our first taste of long-haul rail travel. The rail experience was superb, each train on the journey there and back on time, to the minute, clean and comfortable, as we watched the landscapes of France slip by. And in the Alps, the local trains and cable cars getting us to high altitude with ease, again on time, regular and with exemplary integrated public transport information, on train and station. We are now proud to be part of the 6% club, as compared with the carbon cost of flying.

The journey down was broken in Strasbourg, two half-days to explore the abundant historic delights of La Petite France, the Gothic Cathedral (the fourth-tallest church in the world) and the Rhine-side wildlife. One abundant feature of the attractive floral displays was the Brown Marmorated Stink-bug Halyomorpha halys, new to us, and new to Europe as recently as 1998 when it arrived from the Far East on roof tiles imported for repairs to the Chinese Garden in Zürich. One to watch this, as it is starting to be found in pest proportions on fruit and vegetable crops, both in Europe and North America.

Another non-native insect was Isodontia mexicana, a North American wasp which is now established in Southern Europe, and seemingly at home – last year I even saw it apparently migrating south through the French Pyrenean valleys in September.

And so to Switzerland and the Bernese Oberland, a place of stunning mountain scenery. We were staying in the delightfully traffic-free village of Wengen, overlooked by the Jungfrau massif, from where we had easy access to the higher ground by train and cable car. The alpine meadows around 1200m were blooming again after the first hay cut, with Knapweeds and Willow Gentian, Masterwort and Yellow-rattle, Eyebright and Purple Lettuce, among many others.

 

In perfect weather and a landscape relatively unscathed by agricultural poisons, insects abounded. Butterflies included several Fritillaries, Marbled White and Sooty Copper, among a whole host of other moths, bees, flies, beetles and bugs.

The timing of our trip was deliberate, to visit when the snow cover was the least and hopefully find some of the botanical specialities at high altitude. Highest of all, Jungfraujoch – ‘the Top of Europe’ – at 3454m was almost above vegetation, though the few areas clear of snow had tussocks of hardy flowering grasses. And very little else, aside from begging Alpine Choughs and magnificent views, at least when the clouds parted. Magnificent, albeit worrying to learn that the glaciers are only a shadow of their former selves, melting as a result of climate breakdown.

500m lower down, the summit of the Schilthorn was substantially snow-free, and high alpine flowers were on show, their relatively large flowers (to attract the limited number of pollinators at those altitudes) springing from cushions and mats of rock-hugging foliage.

Again the food-beggars were out, here a Snow Finch, but sadly no Ibex to be seen, although a group of Chamois as we headed back down was some compensation.

The Männlichen cable car from Wengen took us to 2300m, a ridge-top with Snow and Field Gentians, Monkshoods and Grass-of-Parnassus. A Stoat flushed a fledgling Alpine Accentor, and it was here we saw our only Golden Eagle: this part of the Alps is sadly lacking in large predators and vultures.

 

Of course, plants on extensive mountains can be difficult (or dangerous) to search out, so the Alpine botanic garden of Schynige Platte was a final day treat, at the top of an incredibly scenic cog railway, slow and expensive but absolutely worth it. Surely this is the most picturesque botanic garden in the world, with an unsurpassed collection of Swiss native alpine flowers.

As always, the flowers were only a part of the natural festival: Slender Scotch Burnet, Damon Blue, Dusky Grizzled Skipper and Painted Ladies were visiting the blooms, and Common and Green Mountain Grasshoppers and Wartbiters abounded in the flower beds. Presumed migrant Tree Pipits passed overhead, the wader-like piping of Alpine Marmots drifted from the more distant rocky slopes.

  

All the above, and much, much more. As always, a blog like this can only touch upon the absolute highlights of a week, and then only those that fit easily into the overall narrative. But there was so much more: take the the weeping brackets of Fomitopsis pinicola (a phenomenon known as guttation)…

…on a similar theme, a Noon-fly blowing bubbles…

…and on one memorable morning, swarms of unidentified insects in scintillating masses appended to seemingly every tree top…

…the awesome power of the Trummelbach Falls, both over and underground, but impossible to fully capture visually…

…and simply stunning scenery in every direction. And while expensive, as expected, it didn’t cost the Earth too much.

Return to Gunnersbury Triangle: wasp galls on an oak tree

Britain's Wildlife, Travel by Rail

A couple of years after our first, delightful visit to Gunnersbury Triangle (see here), we were again in the vicinity last week, and took the opportunity of a perfect, mellow, sunny autumn day to sample its delights once more. In practice, we spent most of our hour there staring at just one tree, a three-metre Pedunculate Oak on the edge of a clearing, simply laden with galls…

Oak is of course renowned for the number of insects it supports. Many of those cause the formation of galls, abnormal growths in the host plant triggered by its interaction with a gall-causer. While many gall-causers are tiny (and essentially identical without microscopic examination), different species can be told apart by the shape, colour and texture of the galls in which their larvae develop. Those caused by Gall-wasps (Cynipdae) are some of the most distinctive, and all those shown below fall within that group.

Galls can form on any part of the tree, but most obvious are those formed on buds and acorns, and those on leaves, often on the undersides. Perhaps surprisingly given its abundance in recent years, ‘our’ tree had no signs of the large, sticky, woody acorn distortions (Knopper Galls) of Andricus quercuscalicis, but other bud/acorn galls were obvious. By now we are reasonably familiar in Essex with both Ram’s-horn (Andricus aries) and Cola-nut (Andricus lignicolus) Galls, the latter like small, rough, scaly versions of the Marble Gall (Andricus kollari), one of the commonest species everywhere but again apparently missing on this tree. All four of these are relative newcomers to this country (Marble 1830s, Knopper 1960s, Cola-nut 1970s, Ram’s-horn 1997) and have now spread more-or-less widely.

But especially exciting for us was one we hadn’t seen before, the Hedgehog Gall of Andricus lucidus, dramatic pompoms of blobby-ended spokes. Another newcomer, this was first found in Britain in London in the 1990s, but has hitherto shown few signs of spreading far.

London is seemingly the initial focus for many of these new arrivals, presumably in part due to the heat-island effect of the city, keeping winter temperatures 5°C or more higher than in the countryside, and favouring these species originating from more southerly climes. Another contributing factor could be the relative abundance of Turkey Oak alongside native Pedunculate Oak in London’s woodlands. This tree also originates from southern Europe (although the fossil record shows it to have been native here before the last Ice Age), and interestingly all the galls mentioned above (except possibly Ram’s-horn) rely on both oak species for specific stages of their life-cycle. With two generations a year, the sexual generation requires (and forms galls upon) Turkey Oak, while the asexual, late-summer generation is the one we were looking at…

Ands so to leaf galls. There are three widespread and familiar Spangle-galls, the Common Spangle Neuroterus quercusbaccarum, the Silk-button Neuroterus numismalis, and the Smooth Spangle Neuroterus albipes.

All were present on our tree, with Smooth Spangle typically the most scarce. But most certainly not present and correct, because most of the Smooth Spangles, instead of being flattened, smooth, whitish or pink discs, were puckered into the most beautiful flower-like forms.

Another new one for us! But what was it? Eventually, we came up with a name from the internet. Neuroterus albipes variety reflexus. Or perhaps Neuroterus albipes subspecies reflexus. Or just perhaps even a separate, as yet undescribed species, ‘Neuroterus reflexus’. It seems nobody really knows what it is, or even where it is: the normally reliable Fauna Europaea database shows it (as ssp. reflexus) scattered across Europe, but perhaps significantly NOT in Britain or Ireland, nor indeed France, Germany and the Low Countries.

From our observations, we could well believe it is something different to albipes altogether, both from its distinctive, consistently variable shape, but also giving the strong impression of being more strongly associated with the main leaf veins than true albipes.

But there are perhaps other possibilities too. A reflexus gall on one leaf was being closely attended by a tiny 3mm wasp. Completely the wrong time of year and indeed the wrong shape for one of the gall wasps, this looked more like a parasitic species with a long ovipositor. Could the ‘reflexus‘ galls simply be parasitized Smooth Spangles? After all, big fleas have little fleas upon their backs to bite ’em, and little fleas have lesser fleas, and so ad infinitum….

Whatever the truth, a delightful hour of Gunnersbury Triangle magic provided us with new and interesting sightings, and more questions than answers!

#WildWivenhoe Botany & Bug Walks: October – Cockaynes Wood

Britain's Wildlife, Bug & Botany Walks, Cockaynes Reserve, WildWivenhoe

It has been said that ‘Words are easy, like the wind’, but some words we learned on our walk today were not particularly easy, in fact decidedly complex!  Pangaea and Gondwanaland two for starters, not to mention Samara and Parthenogenesis….

The first two cropped up in relation to two beech trees, the European Beech and Southern Beech which stand at the edge of the track down to Cockaynes Wood, the destination of our Botany and Bug walks this month.

These two distantly related species, albeit in different families, share a common ancestor which occurred many millions of years ago on Pangaea, a supercontinent that included all the landmasses of the Earth. That subsequently broke up into Gondwanaland (present day South America, Africa, Arabia, Madagascar, India, Australia, and Antarctica) and Laurasia (everywhere else).  When the separation occurred, the common ancestor went with each landmass, but different climates and natural selection pressures drove the evolution of two now-separate families. It was recognition of such relationships which gave some of the most convincing evidence for the new theory of continental drift, as recently as the early part of the 20th Century.

Our main focus this month was the trees and fungi of the wood, and some of the creatures therein.  Whilst fungi were not particularly plentiful, we found some of interest including a ‘troop’ (yes, it is the collective noun) of Puffballs forming a fairy ring, a Deceiver, Birch Bracket, plus our old favourite the Fly Agaric.  This familiar red and white toadstool grows associated with Birch, and although there are many of these trees in the wood ( so plentiful in fact that they need to be managed to keep them under control, particularly in the open heathland areas), we only found one small patch to admire.  Fly Agaric is renowned for its hallucinogenic properties, and being plentiful in Lapland has been associated with flying reindeer, and the whole red-and-white Santa Claus phenomenon.

A Witch’s broom, often mistaken for a bird’s nest, is often also caused by a fungus, in this case the fungus Taphrina betulina on Silver Birch, one of several microfungi we encountered. Others included the powdery mildew Microsphaera alphitoides on Oak leaves and the rust fungus Phragmidium violaceum, red splodges on the upperside of Bramble leaves, and erupting volcanoes of black spores below.

A few invertebrates were also on show.  A suite of our favourite bugs – Squash, Green Shield and Forest;  a splendid Devil’s Coach Horse beetle which adopted its fiercest pose; Pine Ladybirds; plus a pristine Painted Lady basking in the weak morning sun.  It is hard to believe that these fragile-looking creatures are migratory and able to fly thousands of miles.  Those on the afternoon walk missed the adult, but an eagle-eyed member of the group spotted the caterpillar, itself an amazing beastie.

Spiders and harvestmen (arachnids, not insects, due to not having the requisite six legs) were out in force ready to catch careless flies for lunch.  Some, like the familiar Garden Spider, produce sticky webs to effect this whilst others rely on stealth.  It was also a privilege to see the very active Hornet’s nest in a hollow tree.  These huge, beautiful creatures are much maligned, but if left alone are not aggressive or harmful, and they do much good in gardens and woodlands, helping to control the legions of aphids and other ‘pests’.

And so to another of our words of the day, ‘parthenogenesis’, meaning asexual reproduction.  The wonderfully named Virgin Bagworm, living on assorted fence posts, indeed lives a pure lifestyle.  These weeny wingless moths produce tiny bags which they decorate with lichen, and in which they (all females, no boys allowed, in fact they don’t exist) live for their whole life.  They can produce babies all by themselves with no help from anyone.  Hope it doesn’t catch on!

As for the trees in the wood itself, Sweet Chestnuts were plentiful, in places their leaves sculpted by the excisions of leaf-cutter bees, along with Holly, English Oak and Silver Birch. Hornbeams were at the fruiting stage, producing masses of dangling papery bunches, bunches of winged seeds or ‘samaras’, the last in our lexicon of odd words.

We finished the day with a flourish, seeing a Common Lizard basking in the glorious afternoon sunshine, an amazing aggregation of Scatopsid flies (aka Black Scavenger Flies), plus a veritable collection of Odonata  (dragonflies to you and me) hanging around, catching the last rays of the day: a Migrant Hawker, a few Common Darters, and  several Willow Emerald damselflies, a recent colonist of the British Isles, assumed to be one of the (rather few) upsides of Man-induced climate change, better thought of as climate breakdown, catastrophe even.

As always, many thanks to you all, old friends and new, that joined us .