Monday, December 31, 2012

Last Sunset of 2012 ........

This is the last (watery) sunset of 2012 here in Weardale. The local forecast for tomorrow is dawn-to-dusk sunshine - what better way to begin a new year?

Best wishes to all readers of this blog for a happy, healthy and satisfying 2013.

Saturday, December 29, 2012

Plicatura crispa

I was struggling to identify this fungus, found this afternoon in woodland at Houghall near Durham city, so I posted it on the wonderful iSpot web site and within a couple of hours I received two very helpful suggestions as to what it might be. Sincere thanks to Malcolm Greaves in York for this ID.

It appears to be Plicatura crispa, a fungus with a northern distribution, mostly reported in Scotland. Details can be found at this web site. There's a distribution map here

 The dense clusters of fungi were arranged in tiers and mostly concentrated around burrs on the trunk of the tree, but clearly spreading outwards from there. 

Each individual fructification is quite small - no larger than a thumbnail - but there are often over 100 in a cluster.

The upper surface is brownish-buff, paler towards the edge, and the undersurface is white.

From below ....

 ... the gills have a wrinkly appearance.

I need to go back and collect a specimen now, for a closer look.

Wednesday, December 26, 2012

Alder's Hidden Charms

There isn't a lot of colour in the countryside at the moment but this brightly coloured alder timber, in a small local wood where the owner had been pruning and thinning trees, livened up a dull, grey day. Common alder is a somewhat sombre tree, so it always comes as a surprise the see the bright orange pigmentation that develops in the newly-cut wood. It looks like this particular tree was about thirty years old.

When you look a little close the colour becomes even more striking because the inner layers of bark have a distinct violet hue, similar to the colour of the tree's bud scales when they begin to swell in spring.

Alder timber isn't of much use when dry, other than for making charcoal that was particularly valued for the production of gunpowder. It's a different story, though, if the wood is kept permanently wet because then it is long-lasting. It was the favourite material for making soles of clogs, both because of its toughness when wet and because of its resistance to splitting when small nails are driven in around the edge of the wooden sole. It also made excellent piles for driving into the ground for bridge foundations.

Saturday, December 22, 2012

A Christmas Tale: The Solitary French Horn Player

The last Saturday before Christmas dawned under leaden skies and deteriorated into torrential rain. In need of fresh air and exercise, we decided to walk into Durham city along the river Wear. The rain hammered on our umbrellas and the fast-rising river swirled past, the colour of brown Windsor soup. After almost an hour's walking we had only met one other person who had ventured out into the rain and wind. 

As we rounded the final bend in the river we thought we could hear music, but at first we couldn't see where it was coming from. Then we spotted him - a solitary French horn player standing in the bandstand near the cricket ground, across the river. There was no one else in sight.

We paused to listen while he produced a lively rendition of the hymn 'Thine is the Glory'. When he'd finished he glanced in our direction. We waved, he waved back. We would have cheered, but he would never have heard us across the river, with the sound of the wind, rain and rushing flood water. 

We turned to walk on, as again he struck up a tune: Ray Noble's 'The Very Thought of You'.  

Soon, when we glanced back into the murky December mist he was barely visible and his music was overwhelmed by the sounds of wind, water and traffic as we approached the steps up to the busy shopping centre.

Sheer magic. We don't know who the solitary French horn player was, but he made our day.

Merry Christmas to all visitors to this blog.

Thursday, December 20, 2012


Today's Guardian Country Diary is about an organism that seems certain to benefit from the death of ash trees. More of that later, but first some ash appreciation (amazing, isn't it, how the imminent loss of something makes you appreciate it so much more?).

Ash twigs are surely the most distinctive of any native tree, with those thick grey twigs and charcoal-black buds. The tell-tale ring of bud scale scars that you can see just above the bottom of this twig show that it didn't make a lot of growth last year - there was just a couple of inches of growth before it stopped and developed a new terminal bud. Above those old bud scale scars you can see the scars of the shed-leaf stalks under each resting bud which, with the exception of the terminal bud, formed in a leaf axil when the twig was growing in summer.

Bark of mature ash trees exhibits this quite distinctive criss-cross pattern of fissures. Almost everything about ash is ash grey in winter unless ...

... the tree has been colonised by lichens, which add a splash of colour. A recent survey of epiphytic lichens on ash trees in Sweden recorded 174 different species growing on this species.

This is the downward view that a perching crow enjoys when it looks down from the crown of an ash - in this case one that grows under the old railway viaduct on the Romaldkirk to Cotherstone line (now a footpath) in Teesdale. Here the ashes grow right up to the edge of the parapet, so you get a rare opportunity to visualise the birds' perspective on ash trees.

When ashes grow in places where plenty of rain trickles down the trunk and branches mosses also colonise the twigs. I think this is wood bristle moss Orthotrichum affine which is particularly common on ash.

This is the view from the old railway viaduct mentioned above, where it crosses the river Balder in Teesdale. All those grey tree crowns are ashes. Ash woods often grow best in the rich, moist alluvial soils alongside rivers.

From the viaduct again - those knobbly grey twigs  are actually quite brittle and snap easily. There's a little moth called the ash bud moth Prays fraxinella whose caterpillar destroys the terminal buds of ash shoots, especially in young trees, which promotes the growth of outward-facing buds further down the twig and tends to produce very open-crowned trees (and often low-branching, multiple-stemmed trees if it attacks young saplings)

Ash keys will germinate when they are green but develop dormancy when they ripen - and then it takes a couple of winters to break the seed dormancy. They tend to stay on the tree until spring ....

.... where they're often decorated with hoar frost. Once they do germinate they grow very rapidly and young trees set seed within a decade of growth. My garden is downwind of a large ash and if I didn't keep pulling out all the ash seedlings I'd be surrounded by a forest in no time!

This is a well-proportioned ash in the prime of life. Silhouettes like this will probably disappear from most hedgerows once ash dieback, caused by Chalara fraxinea, runs riot. Many mature ashes display heavy, almost horizontal lower branches that easily snap under the weight of snow and in high winds, leaving jagged holes in the trunk that rot and provide nest holes for birds and roosts for bats.

Ash has the shortest growing season of any native tree, coming into leaf in mid-May and losing its leaves by October. This tree, high on a hillside in Teesdale, is showing signs of autumn on its south-facing side. Ash sheds its leaves in two stages - leaflets first, followed by the leaf stalks on the following day.

The open crown of ash allows plenty of light to penetrate so old trees become swathed in ivy, which vastly increases the value of the tree to wildlife (ivy nectar and pollen for insects in autumn, berries for birds in spring and shelter under those evergreen leaves all year-round). Old trees take a long time to die and ivy-covered specimens often have this stag's antler appearance, with just the ends of branches protruding beyond the coat of ivy foliage.

Ash is far from being the most important tree in terms of the diversity of invertebrate life that depends on it (oaks and birch are way ahead on this score), but these strange growths are the work of the ash gall mite Eriophyes fraxinivorus, which infests the flower buds and prevents seeds forming. Whole trees can be infested. 

This is what healthy ash flowers should look like. The flower buds burst in March, around six weeks before any foliage puts in an appearance. Ashes have complicated sex lives. Individual trees can be male, female or hermaphrodite (with only the latter two types bearing seeds) or they can be one or other sex with occasional hermaphrodite branches. I know of one tree that's all male on the sunny southern aspect and all hermaphrodite on its north side, so only half the tree carries seeds. It's said that trees, and even individual branches, can change sex during their lifetime although I wonder who had the patience to find this out.

I guess we'll lose some rookeries when ashes begin to decline. Rook nests sit comfortably in those open crowns.

When Dutch elm disease took hold elm roots regenerated suckers, so elm is almost is common today as it ever was - it just grows as a shrub rather than a tree, succumbing to its fungal pathogen before it reaches tree proportions. Ash is also capable of regeneration. This pollarded tree, vigorously sprouting new growth, is in a wood near Richmond in North Yorkshire and ......

..... this ash stool is also vigorously sprouting new growth from its roots in the same woods. Will trees attacked by Chalara fraxinea regrow in the same way? No one seems to know yet.

Ash isn't often planted as an ornamental tree, with the exception of this weeping form which is unusual but not particularly graceful. The original weeping ash tree is supposed to have been discovered in woodland by the vicar of Gamlingay in Cambridgeshire sometime around 1760 and it's likely that some of the oldest weeping ashes in gardens are grafted descendants of this original specimen, which has long-since died.

And finally, this is the organism that stands to benefit most when ashes die - King Alfred's cakes fungus Daldinia concentrica, which grows almost exclusively on ash. The late, great mycologist Terence Ingold demonstrated that this strange fungus has an internal biological clock, whereby it only shoots out its spores during the natural hours of darkness, even if you keep it in a light-proof container in continuous darkness. 

Friday, December 14, 2012

Scrumping bears

Whenever I look over a garden wall and see this sight it takes me straight back to youthful scrumping adventures. This is an old and very fine apple tree, in a garden in Durham city, that holds onto its apples right up until Christmas. Fine food for fieldfares, because the fruit is too high up to be pickable (these must be around 15 metres above ground) and will most likely be smashed when it falls and hits the deck. I wish I knew what variety it is.

Genuine native crab apples are quite rare and their fruit stays green and incredibly bitter, but there are plenty of hedgerows around here with feral culinary apples that must have sprouted from discarded apple cores. The skin colour of this one, which is just about to rot, is particularly attractive. 

Molecular biologists, comparing DNA sequences, have shown that the cultivated sweet apple Malus pumila is not descended from crab apple M.sylvestris.  Dr. Barrie Juniper at Oxford University has suggested that the unknown ancestor of culinary sweet apples appeared about 10 million years ago in the Tien Shan forests of Central Asia, where brown bears may have played a role in its evolution. Apple trees always cross pollinate, so apple seedlings are genetically variable and never exactly resemble their parents. Juniper has argued that wild brown bears, known to have a ‘sweet tooth’, would have selected the sweetest, largest fruit as part of their autumn diet. Tough seeds of these superior fruits passed through bears’ digestive tracts unharmed and were dispersed widely. Once humans arrived on the scene their horses, also partial to apples, distributed apple seeds in their droppings as tribes migrated westwards. With the advent of agriculture, about 10,000 years ago, humans began selecting even sweeter varieties from the pool of genetic variability in feral apples and learned to graft them, to perpetuate the sweetest varieties.

Monday, December 10, 2012


I found this picture of the fox that used to sunbath on my father-in-law's garage roof when I was searching back through some old picture files, taken back in 2007. Since then he's had a succession of semi-tame foxes visiting his North Lincolnshire garden. Currently one comes to the patio windows to be fed. Who knows, maybe it's a descendant of this one?

Thursday, December 6, 2012

Not for the squeamish ....

This rather unpleasant looking fish is a hagfish Myxine glutinosa, a member of a very ancient order of jawless fish. They live in muddy sediments and feed on dead and dying fish, sometimes burrowing through their flesh and consuming the fish from the inside out. They've also been found inside of human corpses that have been in the sea for a long time.

I've twice found these unlovable fish on the shore, alive, along the North East coast. The first occasion was at Whitburn Rocks in Tyne and Wear (see pictures at the bottom of this post) and this one was on the Alnmouth end of Warkworth beach in Northumberland. Both locations were close to river mouths and I suspect that had been thrown overboard by fishermen cleaning their catches on their way into port.

Hagfish are blind, although they can perceive light, and they find their prey by scent, using the barbels on their nose. Aside from their feeding habits, their most unpleasant characteristic is that they release massive amounts of slime when they are caught - you can watch this here on YouTube. This is sufficient to deter an attacking shark - see this YouTube video. Even more remarkably, these fish can tie themselves in knots because they have no rigid vertebral column.

This is the mouth, with tooth-like projections inside that the hagfish uses to chew a hole in the body wall of dead fish. That 'knot-tying' behaviour allows it to twist and turn, tearing a hole in its prey.


These are old pictures - I took them in 2007.

You can read more about hagfish here.