Thursday, November 20, 2014

Fine fungi

After a bit of a slow start here, the crop of interesting autumn fungi is beginning to improve, no doubt because of recent rain. We found these three species in the Tyne valley near Wylam today. 
























Variable oysterling Crepidotus variabilis, growing on dead gorse stem





















Beech woodwort Hypoxylon fragiforme, looking very like Christmas baubles. Growing on a fallen tree trunk.



















Purple jellydisc Ascocoryne sarcoides, looking like something that belongs on a butcher's slab. Growing on a fallen tree trunk.


A luxuriance of lichens


Today's Guardian Country Diary is about the way in which the right combination of habitat factors - light, humidity and shelter from the wind - can coincide to provide conditions that favour the luxuriant growth of lichens on trees.

All of these lichen species were festooning just three larch trees in a plantation in Hamsterley forest. The trees were at close commercial spacing in neat rows, but only three on the outside row, in a dip in the ground, carried a dense population of lichens. The next row in, about five feet behind, had a few but the row beyond those, that would have been too shaded in summer when the larches carried needles, had none at all.


This beauty, also shown in the four photos immediately below, is (I think) Usnea subfloridana. Its delicate branches don't respond well to being buffeted by gales but in this sheltered location it hung like beards from the trees.















I've yet to identify the following species but they too covered the lower branches of the larches.



Ramalina farinaceae (?)


Hypogymnia physoides (?)


















Evernia prunastri (?)



Cetraria chlorophylla (?)

























Hypogymnia physoides (?)


















Cladonia fimbriata (?) growing on an old larch cone


Monday, November 17, 2014

Horsetail

 This strange plant is the Dutch rush Equisetum hyemale which isn't a rush at all - it's a member of that strange division of the plant kingdom known as horsetails. We found it yesterday, growing in a ditch beside the disused railway line that now forms the Derwent Walk Country Park in Gateshead.






































To some these flowerless stems must seem like the dullest plants on the planet but they are living fossils, descendants of giant ancestors that once formed a major component of the flora in the Carboniferous swamps, 300 million years ago. The Dutch rushes that we found yesterday grew to about 60 cm. tall but their ancestors grew to tree-sized proportions, some 30 metres tall, and are commonly found as fossils in coal measures. At that time the amphibians were the dominant form of land vertebrate life.



Compression fossils of horsetail stems, like these that we found on the beach at Dawdon on the Durham coast, are easily identifiable as they show the same pattern of grooves and ridges found in present-day horsetails. These stems were about ten times greater in diameter than the Dutch rush stems in the picture above, so if you were to scale up its height in direct proportion this particular fossil ancestor might have been roughly the height of a double-decker bus when it was alive.




This is the distinctive cone of Dutch rush, with that little spike at the top. When it's ripe in spring .....


.... each of those hexagonal sections will separate and elongate on a short stalk, .... like .....





...... these, which belong to the common field horsetail Equisetum arvense. The spores that are released from those yellow sporangia under the hexagons are unique to horsetails ....




.... because each has four long arms called elaters which are curled around the spore during development but are deployed when it dries out and is released, increasing the aerial buoyancy of the wind-dispersed spore.



Friday, November 14, 2014

Nuthatches

When we first moved to Durham, nearly 40 years ago, nuthatches were not very common birds here. I can still remember the first one that I spotted, hammering away at a yew seed wedged into the fissures in the tree near Prebends bridge in Durham city.

Since then they have become very common birds throughout the county and it would be an exceptional day out if we didn't see or hear at least one. I saw these two within ten minutes of each other in Auckland Park, Bishop Auckland, last week - and heard two more there. 

They are now frequent bird table visitors in winter too, and in spring their noisy courtship is a conspicuous feature of woodlands. Their numbers seem to have increased most noticeably in the last decade - although I'd have to concede that maybe I'm also becoming more aware of them.

Which begs the question "why have their numbers increased?". It can't be food supply because their staple food - tree seeds - can't have changed much. Climate change - the favourite driver for everything these days - seems unlikely too as these are hardy little birds. I can't imagine that there has been any decline in any particular predator either.  Maybe bird table feeding has had some effect, but that can't be the only reason as I see them as often in remote places as I do around habitation. 

It's all a bit of a mystery, but it's a delight to watch them feeding at this time of year, when there's a massive abundance of food for them to choose from.








Sunday, November 9, 2014

The sweet chestnut that refuses to die....

Auckland park, in Bishop Auckland, has an interesting collection of old trees and these venerable sweet chestnuts are amongst the finest.




















Some, like this one, are in the prime of life and produced a very heavy crop of chestnuts this year. 

























There are four mature trees that were planted in a line beside a small stream. The ground under them is covered in a thick layer of their serrated leaves, spiny fruit husks and nuts that will keep the squirrels well fed for weeks to come.


























The low-angle late autumn sunshine this morning showed off their fissured bark beautifully. 

























One of the four has been dying for the thirty five years that I've known it. It has shed most of its branches, much of its bark, has been attacked by wood boring beetles and fungi .....

























... and yet every year it sprouts new growth, refusing to die. There could be decades of life left in it yet, unless the roots finally rot and it's blown over by a gale and ......


























...........that would be a pity, because I'd really miss this gnarled old trunk. It's one of the park's characters.




Thursday, November 6, 2014

Thursday's Guardian Country Diary is about this male common darter dragonfly - surely the last of the year - that we saw a few days ago on the banks of the river Tyne near Wylam. 

It settled amongst the fallen autumn leaves and seemed very reluctant to move away from the large patch of flowering ivy that still attracted flies that it was probably feeding on.


















Since then we've had some hard frosts. It will be eight months before we see the next generation hatching out.


Monday, November 3, 2014

Life on a beech


Four different fungi, all on the same decaying beech tree trunk at Bowlees in Teesdale. Dead trees are a wonderful resource for fungi, mosses and many small invertebrates.




















I think this is yellow curtain crust Stereum hirsutum , growing on the cut end of the trunk.


















This is the young stage of the porcelaine fungus Oudemansiella mucida



















... and here it is with the slimy caps fully expanded























... and this is another Stereum species, although I'm not sure which. This is a young stage .....

















.... and this is the same at a more mature stage.




And finally, I think this is the many-zoned polypore aka turkey-tail fungus Trametes versicolor

Wednesday, October 29, 2014

Boletus

I found this beautiful bolete amongst the old oaks in Backstone Bank wood, near Wolsingham in Weardale, this morning. Think it might be an oldish specimen of the cep or penny bun Boletus edulis, judging by the whitish edge to the cap - but not sure.



Monday, October 27, 2014

Fox moth caterpillar

This fox moth caterpillar Macrothylacia rubi crossed our path when we were out walking on Birkside Fell near Blanchland in Northumberland this morning. It will have been feeding on heather.














It's quite late in the year to see one of these in such an active state but the unusually warm weather might have coaxed it out. It's pobably searching for a sheltered spot to spend the winter, before emerging for a brief bask in spring sunshine and then pupating.

There are pictures of the adult moth here.


Thursday, October 23, 2014

Under the skin of a sycamore


Thursday's Guardian Country Diary is about the remarkable range of small invertebrates that live under the flaking bark of old sycamore trees.























When the bole of an old sycamore tree expands the old rigid bark cracks and begins to curl at the edges, while ....























.... a fresh, new layer of bark forms underneath. It might not look very attractive but these bark flakes, some as large as a slice of toast, take a long time to fall off and while they are still attached harbour a remarkable fauna of small invertebrates underneath. Here's a selection, most of which I've yet to ID.



































Millipedes, a hatched moth pupa and some unidentified cocooons 






















Lots more millipedes - these were just a few from under two bark scales - if this sample is representative there must have been hundreds sheltering under the bark of this tree
















A minute scarlet mite



















A rather beautiful little money spider, Gonatium rubens























A huddle of earwigs ....























... that raised their tail forceps in defence when they were suddenly exposed to the light. Male left, female on the right.




































A spider that lives in a silken tent under the bark























Lots of slugs in areas where the bark is permanently damp, where rain water trickles down the tree trunk ..























.... together with snails ......























...... and woodlice















Another moth pupa, that looks as though it hatched successfully.


Sycamore sits low in the league table for tree foliage that supports insect biodiversity - a 1961 research paper on the subject found only 15 species, compared with the 284 hosted by oak (click here for details). But a quick look under the flaky bark of old sycamores casts them in a more favourable light, as a sheltered habitat for a host of invertebrates. 

The few examples shown here were just from a height that I could reach - there may well be a different array of species higher up the trunk and the hosted species most probably vary depending on the aspect (sunny & south facing or shaded & north-facing). Moisture must play a role too because there are well defined runnels where rainwater flows down the trunk from the branches and the bark there is always moist and often very wet. All in all, flaking sycamore bark is probably quite a complex habitat, with many interesting interactions between species that inhabit it.