More tree silhouettes in winter

Graceful silver birches Betula pendula

Sweet chestnut Castanea sativa

Hawthorn Crataegus monogyna. A tough, impenetrable tangle of branches, often with a twisted, fluted trunk when it is given time and space to grow into a tree.

Common lime Tilia europaea. Often has burrs at the roots with a mass of twigs, which have been trimmed in this specimen.

The mass of twigs growing from the burrs at the base of an untrimmed common lime

Beech Fagus sylvatica. Slender twigs with pointed buds.

Elder Sambucus nigra usually grows as a large hedgerow shrub that'sseverely cut back annually and only has a short life span but if it's left alone and given space it will grow into a small, densely-branched tree like this. Old elders have deeply fissured corky bark and twigs covered in yellow Xanthoria parietina lichen.

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Bishop Auckland's magnificent Spanish chestnuts

Some more pictures of the wonderful Spanish chestnuts Castanea sativa in Auckland Park, Bishop Auckland, County Durham that were described in the Guardian Country Diary yesterday.

Not dead yet! Still has living branches that will sprout leaves in spring.

There's a small bird-sown holly tree growing amongst the branches of this one.

The largest bole of a venerable but healthy tree. Spanish chestnuts can live for 400 years.

Winter buds





Flowers and foliage.



Shiny, edible seeds with spiny husks.

Beautiful Bark

Auckland Park, in Bishop Auckland in County Durham, has a fine collection of venerable trees with beautiful bark patterns. 

Hawthorn Crataegus monogyna

Fluted trunk on an old hawthorn ....

.... with an elegant twist

Grey poplar Populus alba. The flat surfaces, between the fissures, are covered with diamond-shaped scars that look as though the bark has been hit with a pick, which is most evident on young trees like the one you can see by clicking here.

The old grey poplars have the most deeply fissured bark of any trees in the park ....

.... with splits so deep that they resemble crevasses 

Young silver birch bark peels away in thin layers (click here for a picture) but as it ages the bark splits and forms flaky plates ...... 

...... like this

Sweet chestnut Castanea sativa, with a bark pattern that resembles raised branching fibres ...

... with deep crevices where all manner of small invertebrates can spend the winter

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.

Fog and Fungi

A while back I posted about threats to the future of the Bishop of Durham's deer park at Auckland Park, in Bishop Auckland in County Durham. Thankfully these seem to have abated, much to the relief of all those who love the place. It's one of our favourite Sunday morning walks - even in the fog.

The park is at its best in autumn ....

.... especially when fog adds a touch of liquid magic to the spiders' webs.

I think it was Oliver Rackham, the noted tree and woodland expert, who once remarked that the only thing more useful to wildlife than a live tree was a dead tree. He was referring to the vast range of organisms - invertebrates, fungi, etc. - that live in or on the dead wood during a tree's protracted afterlife. Whoever manages the park at Bishop Auckland leaves plenty of dead wood for the benefit of organisms that thrive on it - like these tiers of bracket fungi (Ganoderma sp. I think) in the hollow trunk of this dead beech.

Some of the living beeches are under attack by honey fungus and their days are numbered - but there are also plenty of healthy trees and some replanting.

The stumps of old sweet chestnuts host these developing puffballs.

Sycamore, with the black spots of Rhytisma acerinum on the leaf blade.

Some of the living trees have magnificent rings of toadstools around their bases - I guess that these are a mycorrhizal species, that exist in a mutually beneficial association with the trees.

Not sure what these are, on a decaying beech stump. During the prolonged afterlife of the dead trees a whole succession of toadstools appear, some for just a few days.

A Tree-Spotter's Guide to Flowers: 4

Field maple Acer campestre flowers are produced at the same time as the leaves in Spring, like sycamore but unlike Norway maple that opens its flower buds before the leaves expand. They point upwards, unlike sycamore flowers that dangle.

Unlike those other two Acer species, the green petals of the flowers are covered with long hairs. Field maple also produces a lot of nectar (you can see the drops glistening here, especially if you double-click on the image to enlarge) and this attracts small flies that pollinate the flowers. There are eight stamens and a stigma that's divided into two branches.

Oak catkins are produced at the same time as the leaves expand in April. These are male catkins that will release pollen - the female ones that will produce acorns are much shorter, with just a few florets.

Sweet chestnut in full flower, showing the long male catkins. These are produced well after the leaves have fully expanded, in July. This means there's not much time before autumn for the fruits to develop - which is why we never get much of a crop here in North East England unless we get a long, mild autumn.

The stamens on the make catkin of sweet chestnut. The male flowers have a sickly smell.

 

Limes (Tilia spp.) are relatively late bloomers too, opening right at the end of June. They dangle from long stalks that have a single elongated wing attached, that later slows the fall of the seeds and aids their dispersal. Lime flowers produce large amounts of nectar and if you stand underneath a tree when it's in full bloom it literally hums with bumblebees, that find it irresistible.

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