David Attenborough on Richmond Park, London

Nothing much need be added, in light of who is narrating. As a 20-minute long film, it’s something you can readily watch at any point where you have some time going spare. There’s a few good segments on trees, including on ancient trees, deer, deadwood and wood-decay fungi. Really a fascinating watch!

Support the Friends of Richmond Park here.

David Attenborough on Richmond Park, London

Interesting cases of wood-decay fungi

I have been absurdly busy so haven’t been blessed with the time to get some blogging in, though I have been graced with thirty minutes of time this evening so without any further utterings we’ll delve right into the good stuff – trees and fungi (in my usual frenetic and incoherent manner). Plus, listening to some early Hawkwind has really got me in the mood to do something useful!

The cases are all from an absolutely splendid park down in Maidstone – Mote Park. Honestly, if you live anywhere near there, do pay it a visit and explore as much as you can (it’s massive!). The sheer abundance of mature and veteran trees provides for a magnificent display of fungi and, so I am told, there is a need to record the saproxylic insects on site on the many monoliths and moribund trees.

To kick this post off, I take you to a very interesting case of Pseudoinonotus dryadeus on oak – three of them, all of which are within 8-10m of one another and share a crown. All fruitings of the fungus are historic though its presence on all three trees makes for some tempting considerations – namely, the synchronicity of fruiting (are they similar genotypes?) and the means of colonisation (spore or something else?). Indeed, I can only infer some sort of fungal mysticism or sorcery in positing both aspects for consideration (there is no proof of either, per se), though it did make me think. Perhaps it will make you readers think as well! (!?)

Pseudoinonotus dryadeus colonisation senescent old 1
The recipients of the Manchurian Candidate!
Pseudoinonotus dryadeus colonisation senescent old 2
Exhibit one!
Pseudoinonotus dryadeus colonisation senescent old 3
At the base (to the left).
Pseudoinonotus dryadeus colonisation senescent old 4
Quite an old bracket but a bracket nonetheless. Lovely buttressing, too.
Pseudoinonotus dryadeus colonisation senescent old 5
Exhibit two. More brackets and more buttressing.
Pseudoinonotus dryadeus colonisation senescent old 6
Shame these got yanked off, too.
Pseudoinonotus dryadeus colonisation senescent old 7
Exhibit three! SOme glorious buttressing here, yet again. Thus the fungus gets its common name: the Eiffel Tower fungus.
Pseudoinonotus dryadeus colonisation senescent old 8
Old, dead (not really but who cares for semantecs?) but not forgotten.

And then…and then…more Pseudoinonotus dryadeus – literally 100 yards down the same path. Oh how Mote Park delivers! This example also really does demonstrate the magnificent buttressing induced by its decay on oak, as you’ll see.

Pseudoinonotus dryadeus mature oak butt decay 1Pseudoinonotus dryadeus mature oak butt decay 2Pseudoinonotus dryadeus mature oak butt decay 3Pseudoinonotus dryadeus mature oak butt decay 4Pseudoinonotus dryadeus mature oak butt decay 5

Would you then believe it? Essentially opposite (no joke) were two colossal beech trees fenced-off (as if that ever stopped me??!) that, as anyone who has seen mature or veteran beech buttressing all over the place like egg whites pour out of a broken egg when broken too aggressively (nice analogy? – likely not), drew me in. Was I disappointed? Not at all! Ganoderma australe and Meripilus giganteus all over the option.

Fagus sylvatica mature buttressing Ganoderma Meripilus 1
Good cop (right) bad cop (left) – something something pun something something copper beech and tell better jokes
Fagus sylvatica mature buttressing Ganoderma Meripilus 2
The copper beech to the right with roots all over the option.
Fagus sylvatica mature buttressing Ganoderma Meripilus 3
Ganoderma australe and Meripilus giganteus – dual decay. Decay squared? That raises a good thought – is decay by more than one fungus simply a cumulative issue or instead a geometric or even negatory issue (i.e. is decay of two types ‘less serious’ than from one only)? Question galore and no answer. Someone ask an expert!
Fagus sylvatica mature buttressing Ganoderma Meripilus 4
Merip (foreground) and Gano (background). Also plenty of blades of grass for the monocot enthusiasts who stumbled across this blog because I wrote the word monocot.
Fagus sylvatica mature buttressing Ganoderma Meripilus 5
Ganodeerma australe being illuminated by a sunburst.
Fagus sylvatica mature buttressing Ganoderma Meripilus 6
The diddy little brackets further up the stem weren’t blessed with sun.
Fagus sylvatica mature buttressing Ganoderma Meripilus 7
And between some more buttresses there were some more Ganodermas.
Fagus sylvatica mature buttressing Ganoderma Meripilus 8
Onto the plain old beech now. Exquisite buttressing here!
Fagus sylvatica mature buttressing Ganoderma Meripilus 9
Did someone say fungi?
Fagus sylvatica mature buttressing Ganoderma Meripilus 10
Nope – nothing to see here.
Fagus sylvatica mature buttressing Ganoderma Meripilus 11
Nor is there anything to see here. I’m just tired of writing captions!
Fagus sylvatica mature buttressing Ganoderma Meripilus 12
Oh look, finally. Something. Some nice husks. Probably some Ascomycetes on them (Xylaria carpophila).

To finish up, because I’m getting tired and I am up early tomorrow, here’s something to sit on whilst you ponder the plethora of ultimate questions spewed forth from my mind with little restraint – a dryad saddle. The host? Not sure – lots of ash about though one can never rule out sycamore (unless you’re in the middle of a Douglas fir plantation?). These had actually already over-matured, which means you can see dryad saddle (i.e Cerioporus squamosus – named, prior to that, Polyporus squamosus) out there if you look!

Dryad saddle Polyporus Cerioporus squamosus 1Dryad saddle Polyporus Cerioporus squamosus 2Dryad saddle Polyporus Cerioporus squamosus 3Dryad saddle Polyporus Cerioporus squamosus 4

Interesting cases of wood-decay fungi

Trees in the ecosystem pt IV: Trees & arthropods

The arthropods are vast in terms of species, and include ants, beetles, butterflies, mites, moths, spiders, and so on. Therefore, covering the entire spectrum of arthropods in this section is impractical, though the general provisioning by trees will be outlined and species will be used to illustrate given examples.

Many arthropods are considered to be saproxylic in nature – they principally utilise dead woody material (both standing and fallen, in both dead and living trees) as habitat, for at least part of their life cycle, though they may also rely upon fungal sporophores associated with the presence of deadwood, as is to be detailed below (Gibb et al., 2006; Harding & Rose, 1986; Komonen et al., 2000). Of all the saproxylic arthropods, beetles are perhaps the most significant in terms of the proportion occupied of total saproxylic species worldwide (Müller et al., 2010), though saproxylic flies also feature in great numerical abundance (Falk, 2014; Harding & Rose, 1986).

Beetles may be either generalist or specialist in nature (on either broadleaved or coniferous hosts), and they will normally require a host with an abundance of deadwood (or large sections of coarse woody debris) usually over 7.5cm in diameter that resides within an area typically not heavily shaded (Müller et al., 2010; Siitonen & Ranius, 2015). This may be, in part, due to many beetle species (in their adult stage) requiring nectar from herbaceous plants, which would be lacking in woodland with significant canopy closure (Falk, 2014; Siitonen & Ranius, 2015). This means that veteran trees amongst wood pasture and parklands (including in urban areas) may be particularly suitable (Bergmeier & Roellig, 2014; Harding & Rose, 1986; Ramírez-Hernández et al., 2014; Jonsell, 2012; Jørgensen & Quelch, 2014), though this is not at all a steadfast rule as species may also be found abundantly in (perhaps more open) woodland, and particularly where there are large amounts of veteran trees and deadwood – around 60 cubic metres per hectare, according to Müller et al. (2010). Granted, they are found particularly in older (mature to veteran) trees, including within cavities that possess wood mould, water-filled rot holes, dead bark, exposed wood, sap flows, fruiting bodies (of fungi and slime moulds), mycelia of fungi, dead branches, and dead roots (Carpaneto et al., 2010; Falk, 2014; Harding & Rose, 1986; Siitonen & Ranius, 2015; Stokland et al., 2012). Beetle species may also not necessarily associate preferentially with a species (or group of species), but with the conditions aforementioned that are present within a tree (Harding & Rose, 1986; Jonsell, 2012). At times, preferable conditions may be an infrequent as one veteran tree in every hundred (Harding & Rose, 1986).

veteran-oak-tree
A veteran oak tree that is of prime habitat for a variety of organisms.

Despite this, species preference is observed. For broadleaved obligates, heavier shade may be more necessary, and in such instances there is a closer affinity of the beetles with fungal mycelium. Because fungi tend to produce more mycelium in cooler and more humid conditions (though this does, of course, vary with the species), the broadleaved obligates may therefore be found normally in greater abundance where conditions are more suited to fungal growth, and their presence may thus be associated with a canopy openness of as little as 20% (Bässler et al., 2010; Müller et al., 2010). This is, of course, not a steadfast rule, and many open wood pastures may support a great abundance of saproxylic beetles (Harding & Rose, 1986).

It is also important to recognise that many species of saproxylic beetle are reliant upon particular stages of the wood decay process. For instance, species that require fresh phloem tissue will only be able to colonise briefly in the first few summers following on from the death of the phloem tissue (Falk, 2014). Other species require significantly-decayed wood in a particular micro-climate, and even of a particular tree species (Harding & Rose, 1986). There also exist intricate associations between species of fungi and saproxylic insects. Inonotus hispidus, which is usually found upon ash, is the habitat for Triplax russica and Orchesia micans, whilst the coal fungus (Daldinia concentrica), also oft found upon the deadwood of ash (Fraxinus excelsior), is the main provider of habitat for Platyrhinus resinosus (Falk, 2014). The birch polypore (Fomitopsis betulina) is also host to numerous species of Coleoptera (Harding & Rose, 1986); as is the polypore Fomitopsis pinicola (Jonsson & Nordlander, 2006; Komonen, 2003; Komonen et al., 2000). This means that these species may be found where there is a suitable population of the fungus’ host species, where sporophores are present and will likely fruit again in the future, across numerous trees, and for many years. Most beetle species rely on oak more so than other tree species however, as oak generally lives for much longer and thus provides a wider array of different micro-habitats, and possesses increased compositional complexity as a result (Harding & Rose, 1986; Siitonen & Ranius, 2015).

ancient_orchard_malus_inonotus_hispidus4
A fruiting body of Inonotus hispidus on apple (Malus sp.). This fungus not only creates habitat in the wood that it degrades but also is a direct habitat through its sporophore.

Therefore, the loss of suitable habitat through active management programmes (including logging, and felling trees for safety reasons in urban areas) will have a very adverse impact upon saproxylic beetles, though also certain species of moth, and even species associated with saproxylic insects, including parasitic wasps, solitary wasps (which use beetle bore holes for habitat), and predatory Coleoptera (Harding & Rose, 1986; Komonen et al., 2000). Curiously, research by Carpaneto et al. (2010) concluded that trees that were ranked as the most evidently ‘hazardous’ were host to the most saproxylic beetle species, and their removal would therefore have a drastic impact upon local populations. Similarly, fragmentation of woodland patches suitable for saproxylic populations has led to a decline in the meta-populations (Grove, 2002; Komonen et al., 2000), as has deadwood removal in a managed site itself (Gibb et al., 2006). Interestingly, though not surprisingly, ‘deadwood fragmentation’ also has an adverse impact upon saproxylic insect populations (Schiegg, 2000).

Both ants and termites also benefit from the presence of deadwood. With regards to both, nests will usually form at the base of a tree or at an area where there is at least moderate decay – enough to support a viable population (Jones et al., 2003; Shigo, 1986; Stokland et al., 2012). Ants and termites both follow CODIT (compartmentalisation of damage in trees) patterns in relation to how their nests progress, and thus their territory will increase as fungal decay propagates further into the host. Ants will not feed on the decaying wood of the host however, and will simply use the decaying site as a nesting area. Conversely, termites will feast upon decayed wood and essentially control (perhaps by slowing down) the spread of fungal decay in a manner that provides as much longevity of the host as possible for a viable nesting site (Shigo, 1986). In tropical rainforests, termites are in fact considered to be one of the principal means of wood decomposition (Mori et al., 2014), and thus the provisioning of deadwood habitat is absolutely critical. Without decaying wood within trees therefore, ants and particularly termites will lack a potential habitat, and thus where a stand is actively managed populations may be markedly reduced (Donovan et al., 2007; Eggleton et al., 1995). Of course, termites are not necessarily to be desired when they are invading the wood structure of a property, and therefore deadwood is not universally beneficial (Esenther & Beal, 1979; Morales-Ramos & Rojas, 2001) – at least, when human properties are involved.

termites_1_007
Ecologically beneficial? Yes. Economically beneficial? No. Termites can – and do – damage timber-frames buildings, as is the case here. Source: Pestec.

The presence of deadwood may also be beneficial for ground-nesting and leaf-litter dwelling spiders, which can utilise downed woody debris (particularly pieces with only slight decay) for both nesting and foraging (Varady-Szabo & Buddle, 2006). In fact, research by Buddle (2001) suggested that such spiders may more routinely utilise downed woody material when compared to elevated woody material (dead branches and telephone poles) because of the greater array of associated micro-habitats, and particularly at certain life stages – such as during egg-laying, for females (Koch et al., 2010). Furthermore, as fallen woody debris can help to retain leaf litter (or even facilitate in the build-up leaf litter), spider populations are more abundant and more diverse in sites where such woody debris is present (Castro & Wise, 2010). Therefore, where woodlands are managed and areas are clear-cut, spider populations may be markedly reduced in terms of the diversity of species. However, generalist species may benefit from the amount of cut stumps (Pearce et al., 2004). Curiously, Koch et al. (2010) suggest that spiders may perhaps benefit from woodland clearance, because the vigorous re-growth of trees and the higher light availability to the woodland floor (promoting herbaceous plant growth) increases the abundance of potential prey. Despite this, old-growth species will suffer (Buddle & Shorthouse, 2008), and thus the population structure of spider populations may dramatically change.

Soil mites are a further group that benefit from coarse woody debris, though also from hollows and holes throughout the basal region of a tree (including water-filled cavities), and from fungal sporophores and hyphae associated with wood decay (Fashing, 1998; Johnston & Crossley, 1993). Typically, termites will use fungi and insects found within the wood as a food source, and the wood structure itself will provide for an array of niche micro-habitats that are critical at different life stages of a mite. Certain mite species are obligates that associate with coarse woody debris exclusively, and may in fact only be associated with certain species’ woody debris. Additionally, mites may utilise woody debris and hollows within trees to parasitise upon other species using the ‘resource’, with both lizards and snakes being parasitised by mites following their frequenting of such resources. Beetles may also be parasitised, though the mite in such an instance may use the beetle as a means of entry into woody debris (Norton, 1980).

It is not just deadwood that arthropods will utilise, however. Foliage, both alive and abscised, is also of use (Falk, 2014). For example, the ermine moth (Yponomeutidae) will rely upon the living foliage of a host tree as a food source, and the bird cherry ermine moth (Yponomeuta evonymella) is one example of this. During late spring, larvae will fully defoliate their host Prunus padus, before pupating, emerging, and then laying eggs upon the shoots ready for the following year (Leather & Bland, 1999). Many other moth species will, during their larval stage, also behave in such a manner and thus defoliate their host – either entirely, or in part (Herrick & Gansner, 1987). Other species may alternatively have larvae mine into the leaf and feed upon the tissues within (Thalmann et al., 2003), such as horse chestnut leaf miner (Cameraria ohridella). Flies, including the holly leaf-miner (Phytomyza ilicis), will also mine leaves in a similar fashion (Owen, 1978). Ultimately however, the same purpose is served – the insect uses the living tissues of a leaf to complete its life cycle, and fuel further generations.

1280px-yponomeuta_evonymella_on_prunus_padus
Bird cherry ermine moth having defoliated an entire tree. Source: Wikimedia.

Fallen leaf litter, as briefly touched upon earlier when discussing spiders, may also be of marked benefit to many arthropods. Ants, beetles, and spiders are but three examples of groups that will utilise leaf litter as a means of habitat (Apigian et al., 2006). Beetles will, for instance, rely upon leaf litter to attract potential prey, though also to provide niche micro-climates that remain relatively stable in terms of humidity, light availability, and temperature (Haila & Niemelä, 1999). Their abundance may, according to Molnár et al., (2001) be greatest at forest edges, perhaps because prey is most abundant at these edge sites (Magura, 2002). Of course, this does not mean that edges created through artificial means will necessarily improve beetle populations, as research has shown that there are few ‘edge specialists’ and therefore populations usually will go into decline where there has been significant disturbance. Unless management mimics natural mortality events of forest trees, then constituent beetle populations may thus suffer adversely (Niemelä et al., 2007).

With regards to ants, Belshaw & Bolton (1993) suggest that management practices may not necessarily impact upon ant populations, though if there is a decline in leaf litter cover then ants associated with leaf litter presence may go into – perhaps only temporary (until leaf litter accumulations once again reach desirable levels) – decline (Woodcock et al., 2011). For example, logging within a stand may reduce leaf litter abundance for some years (Vasconcelos et al., 2000), as may (to a much lesser extent) controlled burning (Apigian et al., 2006; Vasconcelos et al., 2009), though in time (up to 10 years) leaf litter may once again reach a depth suitable to support a wide variety of ant species. However, the conversion of forest stands into plantations may be one driver behind more permanently falling ant populations (Fayle et al., 2010), as may habitat fragmentation (Carvalho & Vasconcelos, 1999) – particularly when forest patches are fragmented by vast monoculture plantations of tree or crop (Brühl et al., 2003). The conversion of Iberian wood pastures to eucalyptus plantations is one real world example of such a practice (Bergmeier & Roellig, 2014).

Also of benefit to many arthropods are nectar and pollen. Bees, beetles, butterflies, and hoverflies will, for instance, use nectar from flowers as a food source (Dick et al., 2003; Kay et al., 1984), and generally (but not always) a nectar source will lack significant specificity in terms of the insect species attracted (Karban, 2015). Despite this, different chemicals secreted by different flowers, and the toxicity of certain nectar sources to particular insects, means certain tree species may only be visited by certain insect species (Adler, 2000; Rasmont et al., 2005). Tree diversity may therefore be key to sustaining healthy insect populations (Holl, 1995), and where species may prefer to frequent herbaceous plant species the presence of a diverse woodland canopy above may still be very influential (Kitahara et al., 2008). This may be because a diverse array of woody plant species increases the diversity of herbaceous species. At times, pollen may also be a reward, as may (more rarely) a flower’s scent. Karban (2015) remarks that all are collectively dubbed as ‘floral rewards’.

References

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Apigian, K., Dahlsten, D., & Stephens, S. (2006) Fire and fire surrogate treatment effects on leaf litter arthropods in a western Sierra Nevada mixed-conifer forest. Forest Ecology and Management. 221 (1). p110-122.

Bässler, C., Müller, J., Dziock, F., & Brandl, R. (2010) Effects of resource availability and climate on the diversity of wood‐decaying fungi. Journal of Ecology. 98 (4). p822-832.

Belshaw, R. & Bolton, B. (1993) The effect of forest disturbance on the leaf litter ant fauna in Ghana. Biodiversity & Conservation. 2 (6). p656-666.

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Owen, D. (1978) The effect of a consumer, Phytomyza ilicis, on seasonal leaf-fall in the holly, Ilex aquifolium. Oikos. 31 (2). p268-271.

Pearce, J., Venier, L., Eccles, G., Pedlar, J., & McKenney, D. (2004) Influence of habitat and microhabitat on epigeal spider (Araneae) assemblages in four stand types. Biodiversity & Conservation. 13 (7). p1305-1334.

Ramírez-Hernández, A., Micó, E., de los Ángeles Marcos-García, M., Brustel, H., & Galante, E. (2014) The “dehesa”, a key ecosystem in maintaining the diversity of Mediterranean saproxylic insects (Coleoptera and Diptera: Syrphidae). Biodiversity and Conservation. 23 (8). p2069-2086.

Rasmont, P., Regali, A., Ings, T., Lognay, G., Baudart, E., Marlier, M., Delcarte, E., Viville, P., Marot, C., Falmagne, P., & Verhaeghe, J. (2005) Analysis of pollen and nectar of Arbutus unedo as a food source for Bombus terrestris (Hymenoptera: Apidae). Journal of Economic Entomology. 98 (3). p656-663.

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Shigo, A. (1986) A New Tree Biology. USA: Shigo and Trees Associates.

Siitonen, J. & Ranius, T. (2015) The Importance of Veteran Trees for Saproxylic Insects. In Kirby, K. & Watkins, C. (eds.) Europe’s Changing Woods and Forests: From Wildwood to Managed Landscapes. UK: CABI.

Stokland, J., Siitonen, J., & Jonsson, B. (2012) Biodiversity in Dead Wood. UK: Cambridge University Press.

Thalmann, C., Freise, J., Heitland, W., & Bacher, S. (2003) Effects of defoliation by horse chestnut leafminer (Cameraria ohridella) on reproduction in Aesculus hippocastanum. Trees. 17 (5). p383-388.

Varady-Szabo, H. & Buddle, C. (2006) On the relationships between ground-dwelling spider (Araneae) assemblages and dead wood in a northern sugar maple forest. Biodiversity & Conservation. 15 (13). p4119-4141.

Vasconcelos, H., Pacheco, R., Silva, R., Vasconcelos, P., Lopes, C., Costa, A., & Bruna, E. (2009) Dynamics of the leaf-litter arthropod fauna following fire in a neotropical woodland savanna. PLoS One. 4 (11). p1-9.

Vasconcelos, H., Vilhena, J., & Caliri, G. (2000) Responses of ants to selective logging of a central Amazonian forest. Journal of Applied Ecology. 37 (3). p508-514.

Woodcock, P., Edwards, D., Fayle, T., Newton, R., Khen, C., Bottrell, S., & Hamer, K. (2011) The conservation value of South East Asia’s highly degraded forests: evidence from leaf-litter ants. Philosophical Transactions of the Royal Society of London B: Biological Sciences. 366 (1582). p3256-3264.

Trees in the ecosystem pt IV: Trees & arthropods

Ancient Tree Forum summer conference, Epping Forest

A quick heads up that the Ancient Tree Forum summer conference at Epping Forest is now open for bookings at this link. At £50 for the two days it’s certainly worth it, and I can attest to the quality having gone last year to the one in Dorchester.

Expect more additions to this blog next week, though having been very busy lately I haven’t had a chance to get much uploaded!

Ancient Tree Forum summer conference, Epping Forest

Horse damage to mature and veteran beech

Grazing rights on commons must be safeguarded, for these rights are an historical relic of an otherwise aggressively-advancing culture. Indeed, there are a wide range of benefits from grazing, including the ecological, socio-economic and cultural, though the New Forest – and probably many (or all!) other sites where grazing occurs under tree canopies – is also subject to the damage associated with unrestricted grazing.

Certainly, the number of horses within the New Forest, the unrestricted nature of their movement and the lack of safeguarding measures (and probably food) around veteran trees has resulted in some quite substantial (yet currently rather isolated and sporadic) damage to the beech trees. I would expect much of the damage comes during winter, when the horses are searching for food that is not in such great abundance, and luckily (or not!?) I managed to watch a few horses de-barking a fallen limb and the butt of one particular beech tree (whilst another horse was grazing upon the lower branches of holly), in addition to some recent examples of damage on other beech.

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On the left, a horse is feastung upon some low-hanging Ilex aquifolium, whilst on the right a plucky horse tries its luck at beech bark.
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Here, we can also spy another horse stripping a fallen limb of bark, too.
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Notice more historic grazing wounds beneath the much fresher wound currently being created.
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Nearby, this particular beech yields far more significant damage. This damage might have even occurred earlier in the morning.
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The lack of any callus / woundwood growth proves how fresh the damage is.
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One can also appreciate the style of damage, causing by the teeth of the horses as they strip the bark.
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Some flies are themselves grazing upon the sugars of the phloem that is now exposed so extensively.
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In Bolderwood, this beech is accompanied by a sign, which educates members of the public about grazing damage – sort of.
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“Keep the ponies out!”, they ask. Whether tourists bother reading this I do not know, though perhaps it’s a new addition to the tree, which is actually in an area (Jubilee Wood) fenced-off from horses.
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Said with such a long face…
Horse damage to mature and veteran beech

Fungi everywhere on a single declining beech pollard, New Forest (UK)

I was forunate to be able to spend some time in the New Forest yesterday, having driven back from Somerset after picking up a microscope (more on that, in due time). When last down there, which was during mid-summer, I spent a few hours sojourning around the Bolderwood / Knightwood Oak ornamental drive, with specific focus upon the myriad of mature and veteran beech pollards that dressed the roadside. One beech, even then, alluded to fungal parasitism, given its dire vigour and evident crown retrenchment (perhaps associated with ground compaction, given its close proximity to a car park and the Knightwood Oak). Therefore, I paid a visit to this beech, with the hope of finding some fungi – and I wasn’t disappointed!

I’ll actually be honest and say this beech is testament to the ability for the species to provide for many wood-decay fungal species. I really don’t think I have ever seen a tree more covered in fruiting bodies of many species than this one, and we’ll run through the suspected species below. First, we’ll look at the tree as a whole, however, and from the first image I don’t think there’s any debate over its poor condition. Granted, with the impending demise of a tree, weak fungal parasites and saprotrophs can enter, and this alludes to the cyclical aspect of energy transfer. In time, this beech will be the food for other plants and trees, though for now it’s fungal food.

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I wonder how many more years this beech has before its snatched from the throes of life! Probably not many.
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The arrows relate to the various fungal species found. Working clockwise from the tip of the centre, I spotted what I suspect are Hohenbuehelia atrocoerulia, Chondrostereum purpureum, Mensularia nodulosa (confirmed), Exidia plana and Bjerkandera adusta.
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Here, behind a limb adorned brilliantly with one of the ex-Inonotus species, sit some fresh oysters (Hohenbuehelia atrocoerulea). Evidently, they are free from frost damage, suggesting they are probably only a few days old.
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There’s also a younger set emerging just behind this cluster in the foreground!
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Looking down the main stem, here we can observe how Chondrostereum purpureum and Mensularia nodulosa are inter-mingling. On the whole, it appears the Chondrostereum is more limited in its amassed substrate, if the presence of fruiting bodies are anything to go by – the ex-Inonotus species is abundant on the trunk and further up into some of the limbs.
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In this image we can identify how the two species really do run right up to their respective thresholds.
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For good measure, these are older sporophores of Chondrostereum purpureum. In their juvenile days, they’d have been far more attractive.
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Further round the trunk, we enter the sole territory of the Mensularia nodulosa.
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Angling upwards, the slotted nature of the tube layers becomes very evident.
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Down on one of the buttresses, this witches’ butter (Exidia plana) gets comfy amongst mosses. Note that it’s more likely to be this species of Exidia, as Exidia glandulosa is more often found on oak. To discern between the two however, you’d need to inspect some spores under the microscope.
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Looking more closely one can appreciate (I guess…?) why it’s called witches’ butter.
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And up on another limb, we have what is probably Bjerkandera adusta.
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It seems to be ejoying the decay column from the pruning wound and general dysfunction.
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There’s also some gilled sporophores in this one, which could potentially be Panellus stipticus, though they were too sparse and too small to see properly.
Fungi everywhere on a single declining beech pollard, New Forest (UK)

A wintry visit to Greenwich Park, London

Yesterday, as part of our monthly aim of visiting sites across the south east of England, a half-dozen strong group of arboriculturalists made the journey to London’s Greenwich Park – myself included. Indeed, as much of the park consists of deciduous specimens (principally, avenues of Castanea sativa and Aesculus hippocastanum), the park was rather bare in the foliage sense, though such barren canopies did allow us to appreciate the true magnitude of – most notably – some of the veteran sweet chestnuts. The frost-clad ground and crystalline sky provided a similar beauty, and thus we shall begin with one of the most iconic vistas from Greenwich Park – the city skyline.

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As we stood adjacent to the observatory, we could admire – amongst the furor of tourists and scout groups – the sightly perverse beauty of a city. I say perverse, as such artificial and polluted landscapes don’t tend to suit those who don’t consider themselves urbanites, which includes myself.

Of course, we didn’t go there for the view, so let’s get into the main bulk of this account – trees and fungi. There’s no real order to how the below series of images rank, so don’t consider this post a chronological reflection of our trip!

Perhaps the best place in which to start the core section of this post are the huge sweet chestnuts, though we must begin on a rather sombre note. With a species of Phytophthora suspected on site and some of the older individuals exhibiting stunted and chlorotic leaf growth, there is a valid concern for the future of these veterans which is – without doubt – highly concerning. During the winter months, fully appreciating this contemporary issue is difficult, though we did spot some foliage on the floor that was certainly smaller in size than would be typically expected. Alas, this situation should not impact adversely on our admiration of these trees, and should in fact raise attention and draw intrigue to those within the industry and beyond, with an eye to ensuring we continue to care for the current and future populations of veterans. Therefore, promoting the Ancient Tree Forum and their most recent publication on ancient and veteran tree management is critical. And now, for some fine shots of various veterans!

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This veteran sweet chestnut was the first one to greet us as we entered the park from the southern end. Not a bad induction!
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As the city blocks paint the skyline to the right, we get a brilliant juxtaposition between the historic and the contemporary. In such a dynamic and ever-changing landscape such as London, this veteran sweet chestnut acts as a vestige of the old.
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From another angle, the same sweet chestnut as above’s form can be more greatly appreciated. The helical patterns of the wood fibres and bark are as if they have been wound like rope.
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This veteran has seen better days, though still stands proudly by the cafeteria. The ground beneath is woefully compacted, which must be having an impact upn the tree’s ability to function as a living being. Unlike the two shown above, it also doesn’t have a layer of mulch applied around its rooting environment.

Some of the veteran sweet chestnut we came across were also home to two annual common wood-decay fungi – Fistulina hepatica and Laetiporus sulphureus. Without doubt, the state of the fruiting bodies was not good, though when ravaged by time, wind, rain, frost and sun, to still even have a form is respectable! Certainly, a summer visit would have yielded a much greater haul of these two fungi on the sweet chestnuts, so a summer visit is probably on the cards.

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One of Greenwich Park’s many veteran sweet chestnuts with an added extra – a small and rather weathered…
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…you can see it…
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…Fistulina hepatica! Picked off by parasitism before it reached a respectable stature, it still nonetheless produced a hymenium and thus likely produced spore.
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A second sweet chestnut, this time slightly smaller, but again with Fistulina hepatica.
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The state of it is, however, diabolical!
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A smaller and thus younger sweet chestnut, in this instance.
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It sports a fungal fruiting body, nonetheless!
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A chicken of the woods, which is beaten and bruised.
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Another smaller sweet chestnut, and another Laetiporus sulphureus.
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Note how it emerges from behind a bark-covered area.
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Again this sporophore is long beyond its best, though retains a little more dignity in the face of its impending crumble.

Away from the sweet chestnut, there was a variety of other large trees. Below, I share the ones that were home to fungi, through the identification of fruiting bodies. Absolutely, all trees on site are host to many species of fungi, though fruiting is not necessary in many instances, and it certainly costs the fungus energy to create and sustain. To begin, we’ll take a look at the ever-accomodating mature Robinia pseudoacacia in the park, which didn’t disappoint. In all, the population supported three species of wood-decay polypore, as we will see in the below images.

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A very mature false acacia, with a very mature Laetiporus sulphureus fan on the main stem.
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Well, sort of a fan – the remains of!
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I imagine someone yanked this off, as it looks like a rather clean break.
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Very close by, a second false acacia cradles another Laetiporus sulphureus.
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Here, we can see how it’s at the base of the main stem, in place of higher up the structure.
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This second one is far worse for wear!
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A double-stemmed Robinia pseudoacacia, which was once at least triple-stemmed.
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At the base, a senescent Perenniporia fraxinea and a cluster of broken active sporophores can be seen.
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For good measure,here’s a better look at the entire bunch.
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It’s a little disappointing that the fruiting bodies have been damaged, though that doesn’t stop them being Perenniporia fraxinea!
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And a second example of Perenniporia fraxinea on this false acacia, too.
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Right at the base, to the left.
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This one appears slightly different to how it’d usually look (it’s not photogenic!).
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Regardless, a showing of the trama reveals it as Perenniporia fraxinea.
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It looks like the park managers are aware of the decay on this Robinia, as it has already been pruned!
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If you look between the buttresses and into the basal cavity, you can spot a single Ganoderma australe. More were on the other side of the tree, though were old and worn.
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With the sun behind the camera, this southern bracket looks rather pretty.

Steering attention away from false acacias, I now turn towards a focus on the brown-rotting polypore Rigidoporus ulmarius. With both horse chestnut (Aesculus hippocastanum) and beech (Fagus sylvatica) on the site, the chances are that there would have been a few examples of this fungus. Indeed, there were, as we will observe.

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This first example, on horse chestnut, is an interesting one.
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It’s the return of the cavity-dwelling Rigidoporus!
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Away from the wrath of the elements, this sporophore doesn’t have the algal green stain atop and bathes in its own substrate.
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A cutting identifies this specimen as Rigidoporus ulmarius, with the cinnamon tube layer and brilliantly white flesh.
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The second horse chestnut sits in line for the toilets, patiently waiting for soneone to give it the 20p needed to get beyond the toll gate.
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If you want, you can even sit down to inspect this tree!
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This might well be this sporophore’s first season. I wonder how many more years it will see before it gets knocked-off or is aborted.
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Half way up this steep hill, a beech stands seemingly without significant issue.
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Oh, wait – here’s the issue!
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Is that a shade of green?
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From this shot, it looks most probably like Rigidoporus ulmarius. If so, we have two examples in one site of its cavity-dwelling abilities!

Greenwich Park also has a good number of large plane trees (Platanus x hispanica). The most abundant fungus on these trees was massaria (Splanchnonema platani), and there probably wasn’t a plane in the park that didn’t show at least some signs of its presence. However, it was the large plane with Inonotus hispidus that gained much of my eager attention, given I am not often around mature planes with extensive fungal decay.

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A rather lofty plane tree.
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As the crown breaks, we can spot a single Inonotus hispidus sporophore.
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Whether there is an old wound at or around this site is hard to say, though for this fungus to be able to colonise one would expect so.
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Perhaps an old branch stub above the fruiting body?

To round this post off, which has admittedly taken a long time to write, I’ll share some lovely images of a not-so-lovely bird – the parakeet (Psittacula krameri). Plaguing many of London’s parks and beyond, these things produce an utter cacophony and are certainly invasive, though one must admit that they are incredibly photogenic. Below, I share a few examples of where the parakeets were using cavities for shelter.

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A horse chestnut monolith, seemingly vacant.
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Wrong! Enter the parakeet(s).
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This one stands proudly atop a pruning cut.
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Along a plane tree branch, this parakeet appears to be guarding its abode.
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“Oi m8, w0t u lookin’ @???”
A wintry visit to Greenwich Park, London