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Aesculus - the horse chestnuts
Posted on October 20, 2011 by Ash
Posted on June 29, 2011 by Ash
You might not notice anything special about this scene at first glance, but something caught my eye as I drove past. I noticed that a branch had come down, although upon closer inspection that wasn’t everything…
Here’s how I think it happened:
This pine (not a Scots pine, Pinus sylvestris – its needles were too long) had fallen (blown?) over…
…and smashed into a roadside horse chestnut (Aesculus hippocastanum), breaking off half of the tree at a weak union between co-dominant stems with included bark. The resulting nasty wound can be seen in the top-right of the photo; the guilty pine is in the bottom-left.
The half of the chestnut that snapped out fell across the road and hit a tall wild cherry (Prunus avium), breaking a couple of high-up branches.
After hitting the horse chestnut, the pine tree carried on falling across the road. Here is the top section lying on the other side of the road; the middle section that would have blocked the road has been removed.
The pine struck a second horse chestnut on the far side of the road to the first, smashing through a few branches (the lowest in the photograph was probably substantial enough to have been called a co-dominant stem).
I took this photo sat atop the top section of the pine, looking across the road to the pine’s stump and the first chestnut that it damaged. The large wound where the chestnut used to fork can be seen maybe fifteen feet up the stem.
This carnage occurred sometime between Sunday afternoon and Tuesday afternoon. Obviously somebody has been out to clear away the fallen branches and reopen the road, but no attempt has been made to clean up the wounds. The first of the horse chestnuts really wants felling because of the danger it poses to users of the road.
So just to recap how I pieced together the sequence of destruction, I’ve scribbled all over the first photo at the top of this post. The blue hoops ring the leaning pine stump (right of the road) and its detached, recumbent upper section (left of the road). As it fell it struck horse chestnut No. 0856 (red) and horse chestnut No. 0858 (orange). Half of chestnut 0856 was broken off and fell across the road, striking wild cherry No. 0855 (pink). The resulting wounds of 0855, 0856 and 0858 are all circled. Carnage!
Posted on May 26, 2011 by Ash
Horse chestnut No. 32 on the first day of May.
Right at the very beginning of this year, by Broomhead Reservoir in Ewden Valley, I discovered a horse chestnut (Aesculus hippocastanum) with several Daedaleopsis confragosa (blushing bracket / thin walled maze polypore) brackets poking from its trunk. The tree obviously wasn’t in good health; it had recently shed a large branch and much of the tree was dead. I realised that it was suffering from bleeding canker, the bacterial disease which has stormed Britain and now infects roughly half of all our horse chestnuts.
I went to check up on the tree again on the 1st of May and noticed that a number had been painted on it. A few other bleeding canker-infected horse chestnuts nearby had also been labelled. I guessed that these trees were going to be felled soon. Someone else had noticed that these chestnuts were infected!
Maze-like gills on the underside of one of the D. confragosa brackets.
A different type of fungus had appeared a little further around the trunk. I think these are Pleurotus ostreatus (oyster mushrooms).
Here’s the wound where the largish branch had dropped off. I’ve noticed that while bleeding canker doesn’t have a noticeable impact on leaf growth – from a distance diseased trees look pretty normal – infected chestnuts are highly prone to losing whole limbs. The bleeding canker infection must seriously weaken the structure of the tree.
The most noticeable symptoms of bleeding canker are massive bark cracks on the trunk or major branches; these can lead to whole sections of bark breaking away from the tree. I suppose this is how the disease can eventually kill its host. Bleeding cankers like this one are (surprise, surprise) another symptom of… bleeding canker.
Anyway - despite its troubles, No. 32 was still putting on a brave face! It was just beginning to flower at the start of May.
I drove past at the weekend and noticed that the numbered trees had all been felled, so I returned with my camera on Tuesday (May 24th). There isn’t much left of No. 32. A section of the trunk has been left in situ, along with the stump, but there is no trace of the rest of the tree. Everything (branches, twigs, leaves, the lot) has been taken off-site – perhaps to be disposed of in accordance with whatever regulations apply regarding trees infected by bleeding canker.
The stump. It looks like there was some decay in the centre. Was the whole right-hand side of the tree dead? It’s hard to say from the stump.
The stump and the stem, with some of the D. congragosa brackets still attached.
The other end of the stem (top end). Decay is apparent in the bottom-right quarter.
Some of the D. confragosa brackets had broken off and were lying on the floor, where they have begun to go mouldy. I pulled the best remaining specimen off the trunk to take home as a keepsake.
Posted on February 13, 2011 by Ash
Oyster mushrooms (Pleurotus ostreatus) on a dead horse chestnut tree (Aesculus hippocastanum).
I’m sorry if you’re thinking “What? Another post about fungi on a horse chestnut?”, but that’s just how the dice are falling! This particular tree stands not too far from the horse chestnut in the last post, set back a little from the road that runs the length of More Hall Reservoir in the Ewden Valley. It is completely dead, and probably died a few years ago. I don’t think it was killed by bleeding canker, which probably didn’t reach these parts until after the tree had died anyway. Nowadays it’s a big chunk of standing deadwood happily rotting away under a host of hungry fungi, the most noticeable one being the oyster mushroom.
As you can see, the stem is home to a fair few clusters of them. I made a little post last year when I found some of the same on a knackered lime tree (Tilia sp.) on a street in Sheffield.
The oyster mushroom is common on dead trunks and branches of broadleaved species, also occurring rarely on conifers. It can be found throughout the year although it fruits mainly in summer and autumn. Young mushrooms are excellently edible.
This fungus was growing from the base of the tree. I think it’s Xylaria polymorpha, commonly known as dead man’s fingers.
This was also at the base of the tree, tucked between two buttresses. It looks to me like another fungus, but I’ve no idea what species it is. I’ll have to keep a look out for any developments!
Posted on February 10, 2011 by Ash
This post is all about the fungi growing on a horse chestnut tree (Aesculus hippocastanum) with bleeding canker in the Ewden valley. In a previous post all about different fungi growing on a horse chestnut tree with bleeding canker in the Ewden valley, I wrote “…a road running along the northern shore of More Hall Reservoir is lined predominantly by horse chestnut and cherry trees. Virtually every single horse chestnut on this mile-long stretch is in a … bad way, and I am quite sure that bleeding canker is the cause. I think I’ll have much to say on this in future posts!” Well, here’s a start.
First let me introduce you to the tree. It’s in catastrophically bad condition; it has a serious bleeding canker infection and, as apparent from this massive wound, half the tree has broken off sometime last year.
The remainder of the tree is covered in extensive bark cracks symptomatic of bleeding canker. I can’t imagine it being long before the large branch heading out to the right in this photograph breaks off. The orange fungi you can just about make out in this photo – growing on the trunk, the branch, and in the union between the branch and the remaining upright stem – are the focus of the rest of this post.
This photo (taken a month ago on the 8th of January) shows a cluster of mushrooms that sprout from the trunk at about breast height. Here they are at a juvenile stage looking real slimy.
A fortnight later (on the 21st of January) and they’ve turned a darker shade of orange. I’ve identified them – with 99% confidence – as Flammulina velutipes - the velvet stem, velvet foot or winter mushroom (or, according to MushroomExpert.Com, the “At Least Something’s Out In January” mushroom!) It is one of only a few mushrooms around at this time of year, but F. velutipes is “only likely to fruit during warm spells, so if there is snow covering the ground you’re not likely to find it.” True enough, we’ve had no snow since Christmas.
This photo taken with the zoom shows a massive crack on the aforementioned branch and a cheeky little cluster of F. velutipes growing from the exposed dead wood.
The cluster yesterday.
Flammulina velutipes - things you should be knowing: It’s edible and tasty. It can be frozen solid and still produce spores after thawing out. It’s a common species, fruiting from October to March. It’s a saprotroph, growing on the dead wood of broadleaf species – mainly horse chestnut and elms (Ulmus).
This tree deserves your pity.
Next month’s FOTT will be hosted by Rebecca of Rebecca in the Woods. Once again the theme is open and the deadline this month is the 27th. You’ll find the call for the submissions at the Festival of the Trees co-ordinating blog.
Posted on January 23, 2011 by Ash
In the last post I included several photos of bracket fungi on a horse chestnut (Aesculus hippocastanum), which I tentatively IDed as Daedaleopsis confragosa, the thin walled maze polypore or blushing bracket. I am now sure that this is the correct species following a second visit to the tree on Friday afternoon.
My photographs in the last post showed only the upper surface of the brackets, an omission I am making up for with these pictures of the undersides with their maze-like pores.
I found an interesting snippet on a forum earlier: that D. confragosa’s elongated pores (and the random arrangement thereof) are something of an intermediary between circular pores and linear gills. Furthermore: “two years ago we found a collection, where immediately under the older fruitbodies young fruitbodies [had] emerged, so close that they [were] connected. The older fruitbodies had pores, the younger ones gills…”!
I paid more attention to the tree itself on this visit. It’s not in a good way. It has lost at least a couple of its main branches, and at least a couple more are dead or mostly so. Much of the bark is cracked and stained with oozes, symptoms of the nasty bleeding canker disease that may end up doing to British horse chestnuts what Dutch elm disease did to our elms in the 1970s. Regarding the subjects of my photos, D. confragosa grows on dead wood - in this case wood likely killed by bleeding canker.
Higher up the stem, about ten feet from the ground, a different species of fungus is growing on the bark around where two of the tree’s branches have broken off. The tree here is almost certainly dead, and more branches look liable to drop soon. So in summary: much of the tree has been killed by bleeding canker; secondary infections have taken hold in the dead wood; and the tree is starting to fall apart. Crikey.
This particular horse chestnut grows in very narrow strip of woodland on the southern shore of Broomhead Reservoir, separated by a lane from woodland to the south (mainly conifer plantation). A mile to the east, a road running along the northern shore of More Hall Reservoir is lined predominantly by horse chestnut and cherry trees. Virtually every single horse chestnut on this mile-long stretch is in a similarly bad way, and I am quite sure that bleeding canker is the cause. I think I’ll have much to say on this in future posts!
I will be hosting next month’s edition of the Festival of the Trees. Please send your submissions to mail [at] treeblog [dot] co [dot] uk before the 30th of January, ensuring that you include Festival of the Trees or FOTT within the header. ONLY ONE WEEK REMAINS BEFORE THE DEADLINE!
Posted on January 19, 2011 by Ash
I was driving alongside Broomhead Reservoir on the third day of the new year when I spied from the corner of my little eye something beginning with B: brackets, and lots of them. I jumped out of the car and moved in for a closer look.
The tree? A horse chestnut (Aesculus hippocastanum) that clearly isn’t in rude health. It has recently shed a branch (both the scar and the detached limb are visible in the previous photograph). This may well be a consequence of the fungal infection afflicting the unfortunate tree, the visible symptoms of which consist of an impressive array of bracket fungi poking from the lower stem.
The fungi? Well I’m not certain, but I think the brackets may be the thin walled maze polypore a.k.a. the blushing bracket: Daedaleopsis confragosa. Am I right or am I wrong? If you can settle this matter for me please don’t hesitate to leave a comment or blast off an email!
Apparently D. confragosa is especially fond of willows - and these brackets look remarkably like the ones I saw on a willow at Worsbrough Reservoir at the beginning of September. Although at the time I came to a different conclusion…
”Small to medium-sized, kidney-shaped bracket, reddish brown with dirty pinkish white pores on the under-surface, annual; arranged singly or in tiers, on dead wood of broad-leaf trees, favouring willow, birch and beech.” – Jordan, M. (2004). The Encyclopedia of Fungi of Britain and Europe. Frances Lincoln.
Occurs “throughout the year, but sporulating late summer to autumn; frequent.” – Jordan’s Fungi.
Beneath the diseased horse chestnut (as well as a few D. confragosa brackets that had dropped off), I spotted a few decomposing examples of a different type of fungus. Whether these grew around the base of the trunk or were fallen brackets I know not, nor whether they were goodies or baddies from the tree’s point of view. Maybe I’ll come back to this tree later in the year and see if more have grown.
***** I will be hosting next month’s edition of the Festival of the Trees. Please send your submissions to mail [at] treeblog [dot] co [dot] uk before the 30th of January, ensuring that you include Festival of the Trees or FOTT within the header. ONLY TEN DAYS UNTIL THE DEADLINE! *****
Posted on March 14, 2010 by Ash
The imposing Derwent Dam. When the reservoir is full, as it was on Saturday, water pours from between the two towers to cascade foamily down the mighty stone wall.
A spot of super weather was forecast for Saturday so in the morning I headed off to Fairholmes, the visitor hub for the Derwent Valley. The weather didn’t live up to my high expectations, but it wasn’t too bad. At least it’s spring now; winter seems to have been abruptly switched off on the 28th of Feb. From Fairholmes I headed north along the western shores of Derwent and Howden reservoirs, before turning west and climbing up onto the moors to reach the spectacular Alport Castles. Following the high ground south-east, I eventually ended up back at Fairholmes. (Have a go at sussing it out on Google Maps!)
Horse chestnut (Aesculus hippocastanum) buds are amazingly sticky. This one has glued itself to a few stray conifer needles.
This brave young alder (Alnus glutinosa) was growing part-submerged in the reservoir.
The road running up the side of the reservoir is bordered for a few hundred metres by a hawthorn hedge. It has been recently savaged along most of its length, probably by rabbits. They have stripped the bark from most of the stems an inch or less in diameter; anything larger was left unharmed.
Illuminated fruticose lichens (and unilluminated foliose lichens) growing on sycamore (Acer pseudoplatanus) bark on the site of Tin Town. (For the fascinating history of Tin Town, or Birchinlee, see here and here.)
A fine beech (Fagus sylvatica) growing on the site of Tin Town – so it can’t be any older than a hundred years.
This is another beech, but instead of having the lovely, smooth, silver bark typical of its species, this tree was all over disfigured by cankers.
This is the tip of the westwards-pointing spur of Howden Reservoir where it is joined by the River Westend – and look! There is still ice on the surface in the middle of March!
Looking back at Howden, having attained the lofty heights of the moors. There were still plenty of snow pockets around up on the tops. It hasn’t snowed for weeks!
Almost back at Fairholmes – this is the view across the northern tip of Ladybower Reservoir.
Next month’s edition of the Festival of the Trees will be hosted by Vanessa of Vannessa’s Trees and Shrubs Blog. Send in your submissions to treesandshrubs [dot] guide [at] about [dot] com. The deadline is the 29th of March. (The optional theme, in honour of April’s Fools Day, is humourous trees.)
Pests, diseases, disorders, competing growth and unfavourable conditions (a field trip): the diseases
Posted on January 23, 2010 by Ash
Last Thursday my arboriculture class set out from college on a field trip to see a smörgåsbord of pests, diseases, disorders, competing growth and unfavourable conditions afflicting a variety of trees in the vicinity of York and Malton. Some of them were new to me, most I were already aware of, but it was a highly interesting way to spend a day and we got to see some cracking trees. Here’s a quick run-through of the diseases that we saw:
Supermassive sycamore (this photo falls a long way short of doing it justice) with decayed Dryad’s saddles. The one on the floor has fallen off the tree.
Dryad’s saddle (Polyporus squamosus) – A bracket fungi. Described in Jordan’s Fungi 1 as “Large, creamy-brown scaly cap with cream pore-bearing under-surface, annual; parasitic on broad-leaf trees, also on stumps, favouring beech, elm and sycamore.” We only saw old and decaying specimens, but the sycamores (Acer pseudoplatanus) they had grown on were jaw-droppingly colossal - easily the biggest I’ve seen! These ancient sycamores formed an avenue along a road near Birdsall House. I’ve got to go back and get some decent photos of them in the summer before they collapse or get felled for safety reasons.
These crazy patterns are galleries produced by elm bark beetles.
Dutch elm disease – The Big Baddie. The current epidemic is caused by the fungus Ophiostma novo-ulmi, spread by elm bark beetles of the genus Scolytus. It is the most catastrophically devastating tree disease ever recorded in British history. On the field trip we saw a dead elm (Ulmus) replete with bark beetle galleries in the wood beneath the bark.
Cankers on a sycamore.
Canker – There are various kinds of cankers and a variety of causes of cankers. Strouts and Winter 2 define a canker as a “clearly defined patch of dead and sunken or malformed bark”. We saw cankers on sycamore and red horse chestnut (Aesculus x carnea) - a hybrid amusingly described in the Collins Tree Guide 3 as a tree of “rather endearing ugliness”.
Huge ivy-covered canker on a red horse chestnut.
Razor strop on silver birch.
Birch polypore or razor strop (Piptoporus betulinus) – Another bracket-producing fungus, it is restricted to birch (Betula). We saw loads of razor strops on dead and drying silver birches (Betula pendula) in a small piece of woodland that has become waterlogged as a consequence of mining subsidence.
Ganoderma on a veteran English oak.
Ganoderma - A genus of bracket- (polypore) producing fungi that is parasitic on broad-leafed species. We saw a large, dead Ganoderma at the base of a huge and ancient English oak (Quercus robur), but we didn’t identify it to species level. The oak was extremely diseased and its days are sadly numbered.
Slime flux on the same oak.
Slime flux or bacterial wetwood – A bacterial infection causing the host to ooze infected sap from wounds or apparently healthy bark. According to Strouts and Winter 2, bacterial wetwood is “common yet rarely results in overt disease”.
Inonotus hispidus on an ivy-clad ash.
Inonotus hispidus - Another polypore-producer that is parasitic on broad-leaves, particularly ash (Fraxinus excelsior). We saw several dead brackets on an ivy-covered ash growing by a stream.
Fomes fomentarius on silver birch.
Hoof fungus or tinder bracket (Fomes fomentarius) – Like you’d expect, the brackets of this fungus look like hooves. It favours birch – its modus operandi is similar to that of razor strop. We saw several of these brackets on the waterlogged birches.
Posted on June 21, 2009 by Ash
Today was the day of the summer solstice, the longest day of the year; it is also Father’s Day, and we made an excursion to Chatsworth Park, the extensive grounds of the famous stately home, Chatsworth House. At the top of the field where we parked stood a massive oak.
Look at the size of this veteran giant! This photo doesn’t really do it justice, but in the flesh it was awesome-huge. My father is there to lend a sense of scale (and a hug).
The great oak in its entirety, albeit silhouetted by the sun. I think it’s an English oak (Quercus robur).
Proto-conkers. All of the horse chestnut trees (Aesculus hippocastanun) I’ve seen recently are absolutely covered with developing fruits. 2009 looks like it’s going to be a bumper year for conkers!
The River Derwent flows though the magnificent parkland.
The park is studded with hundreds of veteran oaks; this one is a typical example.
The ruins of the old corn mill. The A Taste Of The Peak District website says the mill “ceased operations in 1950 and was badly damaged when a tree fell on it during a storm in 1962.”
Posted on March 5, 2009 by Ash
There are a few tree diseases in the news at the moment. At least two of the newspapers yesterday ran the story that an avenue of 43 horse chestnuts (Aesculus hippocastanum) infected with the bleeding canker disease are to be cut down for safety reasons. The avenue at Barrington Court in Somerset, a National Trust property, is to be replanted with oaks.
Until recently, such Phytophthora bleeding cankers were considered to be uncommon and were only seen in the south of England. However, over the past four or five years, the number of reports of horse chestnut trees with 'bleeding cankers' has increased markedly... The increased incidence of stem bleeding on horse chestnut is not just limited to the UK; the Netherlands, Belgium, France and Germany are also experiencing a similar upsurge.
The other diseases in the news are also species of Phytophthora: P. ramorum and P. kernoviae. Both diseases attack and kill many species of tree and shrub - P. ramorum is the cause of the rather frightening sudden oak death, which was the subject of an early treeblog post two years ago. The two diseases are in the news because the British government has allocated £25 million towards their eradication. According to this BBC article, “Rhododendrons, a carrier of both diseases, are likely to be removed in woodland to combat the problem.” Good. Rhododendron (Rhododendron ponticum) is bad news. It is highly invasive in the UK and takes over woodland through the development of a dense covering of nothing but evergreen rhododendron bushes that stifle and inhibit our native flora and fauna. I would like nothing more than to see rhododendron completely eradicated from Britain, but getting rid of it is easier said than done. It is one stubborn son of a bitch.
Uh-oh. Rhododendron at the edge of my beloved Whitwell Moor (23 May 2007).
P.S. Phytophthoras, sometimes referred to as fungal-like pathogens, are actually protists of the order Oomycetes (water moulds). They are more closely related to plants than fungi.
Posted on January 26, 2008 by Ash
Look here. I've dug out some photos taken last year on February the 3rd. It was a lovely day with a beautiful clear sky. And some of the leafless trees in the Grange area of Edinburgh looked stunning against the wide blue yonder.
European beech (Fagus sylvatica). Smooth silver bark and fine, delicate branches.
Horse chestnut (Aesculus hippocastaneum). Thicker twigs than beech. Notice how the branches droop downwards but have recurved tips.
Lime (Tilia) - whether common, small- or large-leaved I do not know. Notice the dichotomy in size between the main branches and the finer twigs.
Willow (Salix) - I think. I can't remember, but it sure looks like willow.
Posted on May 2, 2007 by Ash
Close-up of a horse chestnut (Aesculus hippocastanum) inflorescence.
Vivid gorse (Ulex europaeus) flowers. I know gorse isn't technically a tree, but it can grow fairly big, woody trunks!
Some species of elm of which I am not quite sure - probably wych elm (Ulmus glabra.
The bark of a close-by elm of the same species growing on a rocky substrate. Quite a big one; must have avoided Dutch elm disease.
Posted on March 9, 2007 by Ash
Hot on the heels of the fall of El Grande, more bad news from the tree world:
The famous chestnut tree mentioned in Anne Frank’s diary is to be cut down. Amsterdam council said on Thursday it has no option but to agree to the felling of the 27 tonne tree which is diseased and could be dangerous if it falls. The tree, which is officially listed, is situated in the enclosed courtyard between Prinsengracht and Keizersgracht.
The horse chestnut (Aesculus hippocastanum), popularly known as the ‘Anne Frank Tree’, featured in the famous diary. The tree was visible from the attic where she and her family hid from the Nazis during the Second World War. It is estimated to be between 150 and 170 years old, making it one of the oldest chestnuts in Amsterdam. For several years the tree has been attacked by the Artist’s Conk fungus (Ganoderma applanatum). Horse chestnut leaf miner moths (Cameraria ohridella) have also been a significant problem. A study in 2006 concluded that 42% of the tree was rotten. Many botanists believe that the tree is close to collapsing, and the owners applied for a permit to carry out a preemptive felling which has now been granted. After the felling, grafts will be planted on the same spot where the chestnut tree is standing and a new tree will grow. A few quotes from Anne Frank’s diary:
February 23, 1944
|© A. Peace 2006 - 2016|