Thursday, September 30, 2010

The Knuckle Bones of Allen Banks

In today's Guardian Country Diary there's an account of a visit to Allen Banks - the spectacular wooded gorge that flanks the River Allen in Northumberland, before its confluence with the River Tyne, west of Hexham. It was only our second visit there and I've been kicking myself ever since for not visiting more often - especially at this time of year, when it's a terrific place for finding fungi. This magnificent specimen of what I think is common puffball Lycoperdon perlatum was growing amongst last year's decaying beech leaves............

..... while this, which I think is sulphur-tuft Hypholoma fasciculare was sprouting from rotting beech roots.


Perhaps the most curious feature, though, was a strange artifact that can be found on a high bluff at the end of the path that climbs up the west side of the valley, before the steep descent down towards the river, in the green patch of  moss visible in the left foreground in the photo above. At this point the view ahead and far below, of the densely wooded gorge that leads upstream to Plankey Mill, is truely stunning but .....

.... if you can take you eyes off the view for a moment and happen to glance down at your feet you soon realise you are standing on something rather strange......... 

.......... a platform made of sheep knuckle bones, hammered into the path and worn smooth by passing feet. Does anyone out there know more about this weird and slightly macabre feature of this woodland walk?

Tuesday, September 28, 2010

Elder - the Elixir of Life?

There seems to be a fine crop of elder Sambucus nigra berries in our local hedgerows this year. John Evleyn, the 17th. century writer, gardener and diarist, was a great fan of this ubiquitous hedgerow tree. “If”, he wrote, “ the medicinal properties of the leaves, bark, berries,&c., were thoroughly known, I cannot tell what our countrymen could ail, for which they might not find a rememdy from every hedge, either for sickess or wound. The inner bark of elder applied to any burning takes out the fire immediately; that, or in season, the buds boiled in water-grewel for a breakfast, has effected wonders in a fever; and the decoction is admirable to assuage inflammation. But an extract may be composed of the berries, which is not only greatly efficacious to assist longevity, but is a kind of universal preventive against all infirmatives whatever; and of the same berries is made an incomparable spirit, which drunk by itself, or mingled with wine, is not only an excellent drink, but admirable in the dropsy. The ointment made with the young buds and leaves  in May with butter is most sovereign for aches, shrunk sinews &c., and the flowers macerated in vinegar not only are of a grateful relish, but good to attenuate and cut raw and gross humours”. All of which may go some way to explaining why my maternal grandmother, who used to make some pretty potent elderflower champagne and elderberry wine, lived to a ripe old age...... although more recent research and opinion has been more circumspect about the safety of some of the folk medicine attributed to this plant. 

Elder shoots grow remarkably vigorously in their first year and I have vivid childhood memories of cutting these, hollowing out the pith and using them as pea-shooters. The hollowed-out twigs have also been used to make flutes and the generic name Sambucus supposedly comes from the Greek (?) sambuca, a musical instrument – although the word was originally applied to a stringed instrument rather than one that you blow. Elder pith, dissected from the centre of the stems, figured in my education when I was at school, for demonstrating electrical charges and for holding plant specimens that were then thin-sectioned for microscopy by hand, using a cut-throat razor (can you imagine Health and Safety allowing that in a school today!)

Recently elder as a natural resource has undergone something of a revival, with the popularity of elder flower cordials and elder flower presse, which has created an unprecedented demand for the inflorescences. Nice to see that at least some of the potential of our native biodiversity is being realised…..

Sunday, September 26, 2010

Cock's Foot Grass Fail-safe Mechanism

The leaves of plants are wonderfully adaptable structures and, in addition to their normal photosynthetic role of trapping energy from sunlight and using carbon dioxide and water to produce sugars, they have evolved a wide variety of functions, ranging from the tendrils of peas to the showy petals of flowers, both of which are highly specialised derivatives of leaves. Sometimes these specialised structures revert to their original form, giving a  clue to their origin, and that's the case with this peculiar seed head of cock's foot grass Dactylis glomerata, which I found beside an arable field near Corbridge this afternoon. On the right you can see a normal seed head, dried by the sun and probably having already shed its seeds, leaving behind the papery bracts (known as glumes) that formed the grass floret when it was in flower and enclosed the stamens, stigma and ovary. The glumes are highly reduced, modified leaves but in the seed head on the left they have reverted to being normal leaves, becoming green and elongated, so each of the grass florets has become a miniature grass plant - a clone of the parent plant. This kind of behaviour, known as pseudovivipary, is quite frequent in late-flowering plants of cock's foot that bloom too late in the season to produce seeds and so use this fail-safe mechanism to produce a cluster of small clonal plants in the seed head instead. You can see florets in various stages in the reversion process - some are just going green, others are already fully-formed miniature grass plants. Eventually the stem bearing them will bend under the weight of the sprouting clones and it will fall over - and when That happens those miniature copies of the parent plant will touch the soil and root.

Saturday, September 25, 2010


It's three and a half years since we last drove through the Stang Forest, on the road from Barnard Castle in Teesdale to Reeth in Swaledale, so it was a bit of a surprise today to find that most of it had disappeared - or, more precisely, had been converted into logs that were waiting to be transported away. In the past we've stopped here quite often to follow a trail through the forest rides to Hope Scar - a cliff where, from a height of  450m. a.s.l. you can view a magnificent landscape away to the north. Now that the trees are gone you don't need to do that any more and for the first time in a generation you can enjoy the view from the road as you crest the top of the hill.

This is the lower part of Teesdale and the valley of the River Greta, bathed in every-shifting patches of sunlight. In the foreground lies what's left of this part of the Stang forest - great piles of branches. Double-click on these three images for a bigger panoramic view - I've loaded them in a slightly larger size than usual.

Almost directly to the north, 6km. away and in the centre of this picture lies the market town of Barnard Castle (see Adrian's Images blog for some fine pictures). Right centre is the famous Bowes Museum, modelled on a French chateau and filled with art treasures and an amazing mechanical silver swan automaton. To the left of that are two small wind turbines that power the GlaxoSmithKline pharmaceuticals plant, while the very large wind turbines on the horizon are at Tow Law, 30km. distant. 

Turn your eyes 90 degrees to the east and Middlesbrough and the cooling towers and chimneys of industrial Teesside can be seen, away on the coast, about 40 km. away. One of those tall objects on the horizon, just above the farm gate, is the famous transporter bridge - the last bridge across the River Tees before it reaches the sea.

Now that all the trees have been felled you can admire these unimpeded views from the brow of the hill....... but don't take your eys off the road for too long, because it's a 14% descent with double hairpin bends on the way down.

Back at the top of the hill the spruces may have been felled but their progeny are already growing away - no doubt the whole forest will soon be replanted, but this seedling wasn't wasting any time.

Wednesday, September 22, 2010

Plant Public Enemy no.1

Japanese knotweed Fallopia japonica tops the table of alien, introduced plants that have become invasive weeds in Britain. Its phenomenal capacity to spread via deep, tough underground rhizomes and its resistance to herbicides, coupled with its tendencies to undermine building foundations, footpaths and roads, have created thriving businesses that specialise in trying to keep it under control. Introducing the plant into the wild is an offence and although it's not illegal to cultivate it in a garden, disposing of it when it begins to overwhelm your plot is a major problem, as Japanese knotweed-contaminated soil is classified as controlled waste and has to be removed by specialist companies. In the past much of the spread of the plant has probably been due to gardeners dumping plant waste, beside roads, rivers and canals. The fact that mortgage lenders are now refusing to lend to buyers of houses with Japanese knotweed in their garden should be sufficient deterrent for anyone contemplating planting it in their plot.

Since our Victorian ancestors first introduced it into their landscaped gardens it has spread around the country via fragments of rhizome in soil, especially in urban waste ground where it often forms four metre tall forests. Apparently, 137,500 tonnes of contaminated soil had to be removed from the London Olympics site alone, before construction could begin and, nationwide, about £150 million is spent every year trying to  control Japanese knotweed. One ray of hope for those seeking to bring it under biological control is that trials of a plant psyllid bug called Aphalara itadori, recently approved for release into infested areas, indicate that this insect could weaken the plant and make other forms of control, like herbicides, more effective

So, with all its destructive tendencies, is there anything positive to say about this aggressive invader? Well - excuse me while I reach for my flak jacket - there is. It's a magnet for honeybees. This fine specimen, that I photographed last weekend growing beside a pavement in Newcastle, near the Ouseburn, was humming with them. It's an ill wind, etc., etc................. 

Friday, September 17, 2010

Slippery, even when not wet...

This is one of the easier toadstools to identify - porcelaiine fungus Oudsmansiella mucida. Conveniently, it's almost always found growing in only one place, on dying beech trees Fagus sylvatica, which narrows down the identification possibilities somewhat.

The other defining characteristic is a permanently wet-look cap, covered in a layer of slippery mucilage that gives it the appearance of the finest quality porcelaine - for a day or two, anyway.
The young, developing toadstool produces so much mucilage that it sometimes drips off, as it's doing on the two lower specimens here. Photographed on a fallen beech tree near Blanchland in Northumberland, earlier this week...

Wednesday, September 15, 2010


If you're small, edible and confronted with a hungry carnivore your options are few. You can keep very still and hope you won't be noticed, run or take the bold option - stand your ground and try to intimidate your tormentor, which is exactly what this elephant hawk-moth Deilephila elpenor caterpillar did when I poked it with a grass stem. We found it in late afternoon (Deilephila means 'lover of evening') on the fellside near Blanchland in the Derwent valley, where it was climbing a rose-bay willowherb stem in preparation for another night's feeding.

The caterpillar was over three inches long, close to being fully fed. Notice the curved tail spike (not very menacing) and the four distinctive eye spots at the other end, which begin to become more menacing when the caterpillar realises it's under threat.

At that point it retracts its front three segments (that are longer and narrower than the others and have some resemblance to an elephant's trunk when it's feeding. This concertina-like contraction forces segments four and five, immediately behind and marked with the eye spots, to swell ............ and now those 'eyes' begin to look much more intimidating.....
.... especially when you look at it from this end, where you can compare its comparatively small real head with the false head formeed by swollen segment four.

Provoke it a little more and it will release its grip with the true legs at the front and, clinging on with pro-legs at the rear, wriggle violently like a snake. At this point its attacked will either be preparing to eat it anyway or will have been sufficiently intimidated to look elsewhere for a meal.

This is the commonest hawk-moth in the UK. You can find images of the adult insect at the excellent UK Moths web site.

Monday, September 13, 2010


I found this very attractively marked herald moth Scoliopteryx libatrix resting on a leaf while I was picking broad beans at the weekend. According to the entomologist L. High Newman in his British Moths and their Haunts (1952) it was given its common name in 1782 by Moses Harris, author of several exquisitely illustrated and much sought-after entomological works. Newman wrote "It is fairly obvious how the association grew in his mind as he studied the pattern and coloration of the moth; there is something reminiscent of the intricate combination of rich colours, red, purplish brown and gold, that one expects in the design of a heraldic emblem". I'd always assumed that it was called the herald for a quite different reason - this is one of the very few moths that hibernates as an adult and emerges again in March, as a herald of spring. Martin Wainwright, in his blog Martin's Moths, recently speculated as to which might be the longest-lived moth in Britain. The herald must surely be a contender. It hatches from the pupa in late August, feeds on autumn flowers like ivy, overwinters in some sheltered place (Newman cited 'nooks and crannies in old brickwork under bridges' as a good place to look for it), breeds in Spring and can still be found at the end of May - nine months in total.

For a tenuous link between this moth and the pointillist painter Georges Seurat, click here.

Sunday, September 12, 2010


According to Ray North in his excellent, entertaining book Ants (Whittet Books 1996) "Red garden ants are the Tarzans of the ant world, and can drag four times their own weight". That suggests that this one, dragging a dead spider through a tangle of grasses, was probably at the limits of its capacity. I watched it for ten minutes, hauling its prey over and under grasse stems, then left it to its exertions. There was no way that it was ever going to reliquish its capture. Inspirational.

Saturday, September 11, 2010

Tales From the Herbarium

There's a delightful Country Diary in the Guardian today by Derek Niemann about Gamlingay Great Heath in Cambridgeshire, that reminded me of a fascinating historical artifact linked to this location that I came across a few years ago.

Once or twice each year, I delve into the darkened corners of our herbarium in the basement of Durham University’s School of Biological and Biomedical Sciences to dig out a few plant specimens for an undergraduate tutorial. The herbarium is permeated by the faint smell of mothballs and lined from floor to ceiling with cupboards crammed with foolscap manila folders containing thousands of pressed flowers.

It’s a relic of a more romantic age in science, when botanists spent long summer afternoons roaming woods, heaths and hillsides in search of rare or unusual plants, trying to make sense of their relationships and unpredictable distributions. Whenever I go down to the herbarium I can’t resist taking a peek at one particular specimen of bracken fern labelled, in elegant, flowing handwriting, Pteris aquilina Gamlingay Cambridgeshire 17th. August 1831 J.S. Henslow.

It’s the signature and date that’s interesting, not the specimen. John Stevens Henslow, Reverend Professor of Botany at Cambridge University, amassed a personal herbarium of thousands of sheets of pressed plants. Somehow this single stray specimen found its way into the Durham University herbarium. And on the day that he collected it Henslow might have been wrestling with an urgent decision that - unbeknown to him - would dictate the course of history.

Just a few days before, on August 13th. 1831, he’d received a letter asking him to recommend a suitable gentleman ship’s naturalist to accompany Captain Robert Fitzroy, captain of HMS Beagle, on a circumnavigation of the world. Henslow, the finest field botanist of his day, would have been the prime candidate but family responsibilities stood in his way. His next thought was to nominate his brother-in-law, Reverend Leonard Jenyns, but he declined in favour of tending to the spiritual needs of his parishioners. So by the end of August Henslow had offered the job to Charles Darwin, his student protégé at Cambridge. The rest is (natural) history.

I like to imagine Henslow mulling over the problem of who to nominate while he botanised through Gamlingay Woods on the summer day when he collected the bracken specimen. If Henslow, a creationist until the day he died in 1861, or his cleric brother-in-law, had sailed with Fitzroy it’s unlikely that they would have come up with a theory of evolution. Charles Darwin’s date with destiny would never have arrived. It would have been left to some other scientist, in another place and at another time, to provide the theory that underpins all of modern biological science.

For informatio on another historically interesting herbarium specimen click here.

Friday, September 10, 2010

Gastric Russian Roulette?

Mild wet weather has produced plenty of toadstools that I can use to test a recently-purchased copy of Paul Sterry and Barry Hughes' excellent Collins Guide to British Mushrooms and Toadstools. First up was this fine specimen of what I'm pretty sure is a shaggy parasol, which now goes under the name of Chlorophyllum rhacodes. An awful lot of names have changed since I last took a serious interest in toadstools; last time I looked it was Lepiota rhacodes.

It was growing in a oak woodland on the outskirts of Durham city. From this low angle you can see the double ring under the cap and the smooth stem that lacks the scales of the true parasol mushroom, Macrolepiota procera. Both species are edible and the true parasol is said to be excellent, but apparently shaggy parasols cause stomach upsets in some people.There's a surprising number of smaller parasol-related species, collectively known as dapperlings, of variable edibility, including one - Lepiota brunneo-incarnata that's deadly poisonous and contains the same toxin as death cap so, as with all toadstool eating, accurate identification is essential.

I'd always assumed that the brightly coloured Russula species were at best inedible and most likely poisonous but this one, the ochre brittlegill Russula ochroleuca is described as being edible in one of my older field guides - but it is very similar to other much less palatable brittlegill species - and therein lies the problem for the novice mycophage like me. How can you be certain that you're not playing Russian roulette with your gastric system when you venture into the world of toadstool eating? Even some of the supposedly edible species can be treacherously upsetting to some sensitive individuals.

Fortunately the Collins Guide is very good for identification and there's another - John Wright's Mushrooms in the River Cottage Handbook series - that provides and excellent and entertaining guide on what to eat and what to admire from a distance. He has some wonderfully lurid descriptions of the effects of poisonous species, that underline the old adage that 'if you're not certain what it is, don't eat it'

Wright is the most recent in a long line of mycologists advocating the pleasures and benefits of eating wild fungi. I have a fascinating copy of the second edition of a book published in 1847 by Charles David Badham M.D. entitled A Treatise on the Esculent Funguses of England containing an account of their Classical History, Uses, Characters, Development, Structure, Nutritious properties, Modes of cooking and Preserving etc., - all covered in 152 anecdote-filled pages and illustrated with 12 hand-coloured plates, of which one - showing a parasol mushroom - is reproduced below. Having travelled in Europe and seen fungus markets and the enthusiasm for eating wild toadstools in Italy, Badham became a passionate advocate of toadstools as food for the poor and described the purpose of his book as being "to furnish the labouring classes with wholesome nourishment and profitable occupation".

Badham had given up his profession as a doctor, perhaps wisely as he had once raised eyebrows by setting the irregular heartbeat of an ailing patient to music, and had taken holy orders, becoming much moved by the plight of those affected by the great potato famine of 1845-52. In his book he writes "In such rambles [you] will see, what I have this autumn (1847) myself witnessed, whole hundredweights of rich wholesome diet rotting under the trees; woods teeming with food and not one hand to gather it; and this, perhaps, in the midst of potato blight, poverty and all manner of privations, and public prayers against imminent famine". He was, of course, right: wild fungi can be a wonderful potential food source, provided you really know what you're eating.................. but I 'm still not absolutely sure about that yellow-capped Russula in the picture above. Dare I eat it? Maybe not......

 Badham died in 1857 and the manner of his death doesn't seem to be recorded but, given the vagueness of some of his descriptions in his book and the shortage of accurate illustrations, you can't help wondering.....

You can download a digital copy of his book here.

The plates in Badham's book only bear the name of the lithographer, not the artist who was Anna Maria Hussey, a notable mycologist in her own right and sister to the tutor to Charles Darwin's sons.

Thursday, September 9, 2010

Embarrassment of Riches

There has been a major emergence of craneflies here recently and many - like the one in this photo - have almost instantly fallen victim to the orb webs of diadem spiders Araneus diadematus. This one had slung its web just at the right height above the grass to catch these gangly insects, that tend to flutter close to the ground when they're laying eggs amongst grass roots. Craneflies are easy victims and this spider had caught several.

When I disturbed the spider in the act of shrouding its latest victim in silk it raced back to the top of the web, to its lair amongst the ragwort seed heads, where its colour provided almost perfect camouflage and where it already had a ladybird in its larder. 
Diadem spiders' webs suffer a lot of wear-and-tear and soon become deranged, only lasting for about a day before the owner eats the old one and spins a replacement ........... so what does it do with its previous day's coccooned, uneaten catch? Transfer it to some temporary store somewhere? I'll have to get out there and have a look...

Wednesday, September 8, 2010

Sea Aster

Sea aster Aster tripolium comes into flower just as most other saltmarsh plants, like sea lavender and sea pink, are past their best, and it continues to flower well into early autumn. This fine specimen was one of many flowering on the saltmarsh at Warkworth recently. It's a very variable plant, tolerant of a wide range of conditions. On the saltmarsh it's periodically inundated with sea water during spring tides and it grows in extremely saline mud. Salt-tolerant plants like this are classified as halophytes.
In other places it tolerates brackish conditions. I photographed this population of the plant on the banks of the Tyne last week, seventeen miles inland from the coast, near Newburn near Ryton Willows Local Nature Reserve. The river is still tidal at this point and here the water must still be only slightly salty, compared with the coastal conditions. The plants here are much taller, more on the scale of garden Michaelmas daisies, which may be because the plants are inundated twice a day and grow on sloping river banks, so it's more of a struggle to keep their heads above water, unlike the saltmarsh plants that grow on an almost flat surface and are only infrequently flooded during very high tides.

There has been a significant amount of research interest around the world on this species in recent years, because of its potential as an animal fodder crop that will grow on very saline soils, with the potential to return land to productivity after it has suffered salinisation through excess irrigation .

Tuesday, September 7, 2010

Something to Celebrate

Much that is reported in the media about wildlife is bad news - usually about catastrophic declines in species abundance, so the rapid northwards extension of the range of the speckled wood butterfly has been somewhat under-appreciated. This butterfly was known in Victorian times as the Wood Argus or Wood Lady and in the 1870 edition of his History of British Butterflies the Rev. F.O. Morris described it a being "...a common species in all parts of the country, from the extreme north to the extreme south..." but it seems that by then it was already declining in the north. By 1986 T.C. Dunn and J.D. Parrack, in their Moths and Butterflies of Northumberland and Durham  lamented that "We must now consider it to be extinct in out two counties, but it still survives in Yorkshire and it is theoretically possible for it to return". I don't think I'd seen one of these delightful insects in County Durham until about five years ago, although I'd occasionally seen them in North Yorkshire, but now they are just about everywhere I look. They arrived in woodlands around Durham city about three years ago and are now so frequently seen that the novelty has already worn off. They have even turned up in my garden on several occasions this year, where I hope that their larvae might make inroads into the common couch that is one of their food plants, along with cock's foot grass and Yorkshire fog.

The speckled wood's ability to produce two generations a year and overwinter as a larva or a pupa must have some bearing on the speed that it establishes itself once it arrives. This is a species where the males are highly territorial and in the ten minutes that I spent watching the individual in these photographs it twice fought short but furious aerial dogfights with an intruder, spirally upwards before returning each time to this sunlit leaf once it had seen it off; a remarkable display of aggression in such an apparently fragile insect. The butterfly literally defends its own personal patch of sunlight, where it poses to attract the attention of a female. Dr Paul Whalley, an entomologist at the Natural History Museum described this territoriality in detail in his book Butterfly Watching in 1980 and suggested that the males probably scent mark their territory. Describing six contesting the same patch of sunlight, he wrote "They flew in an up and down, follow-my-leader fashion which resembled a well-drilled dance routine". Male and female speckled woods are hard to tell apart but the artist and naturalist David Measures came up with a sure-fire solution to the problem in his book Bright Wings of Summer. "Unless you have a male and female side by side it is difficult to distinguish the sexes by the markings" he wrote, but noted that it's 'undoubtedly a cock if it flies up at everything that passes, in true territory-claiming style..." Measures' book, published in 1976, is full of delightfully spontaneous watercolours of butterflies, produced during a decade of patient and meticulous field studies of butterfly behaviour, that perfectly evoke the vibrancy of these wonderful insects - it's well worth reading if you can find a copy.

Monday, September 6, 2010


There are few more pleasant ways to idle away an afternoon than to indulge in a spot of beachcombing, discovering what the falling tide has left behind, and when we arrived at Warkworth beach last Saturday lunchtime the tide had just turned, leaving a trail of marine artefacts, like the crimped pie-crust carapace of this edible crab .....

... and the saw-toothed carapace of a shore crab.

Recent rough seas had scoured the sand and cast up thousands of these sand mason worms, with their tubes constructed from grains of sand ....

... but this dog whelk, with its tough, thick shell may have been rolling around in the surf for weeks.

This is a mollusc that doesn't belong on the shore at all - it's a grove or brown-lipped snail Cepaea nemoralis, which is an air-breathing species that lives amongst the marram grass on the sand dunes behind the beach. Maybe a bird caught it and dropped it on the beach, or it might have been dislodged when a spring tide eroded the edge of the dune. This species comes in a variety of background colours and banding patterns, but many on the dunes here are either pure yellow or sometimes pink.

This is the delicate mauve interior of the rayed trough shell, which is decorated with markings ....

..... like the rays of the setting sun on its outer surface.

Banded wedge shells come in a range of colours, including brown and purple, but the pure yellow ones are particularly attractive.  

The star find was this tower or auger shell, Turritella communis. It's common enough around much of Britain, especially on the west coast, but this is the first time that I've found it here in thirty years of walking along this beach.

And finally, a modern archaeological curiosity - a clay pipe. I wonder who lost this, and how long ago - maybe a fisherman who dropped it overboard? Whoever it belonged to, it must have remained buried in the sand until a convergence of rough weather and high tide scoured it out and left it on the tide line.

For more beachcombing on Warkworth beach, visit