Kveldssanger

Look at p64 and p68 for a species list.

Some of the monetary values provided at the start of the report really do show that we should be caring for our trees in a manner that pursues their retention (where feasible).

Evening, London recently had an i-Tree report completed and published. A great read, and there's some really interesting stuff in there. Read it here and share it.

The ones around here are feral, unfortunately.

Hi all, A heads up that this beast is now out. https://www.springer.com/gb/book/9789401773942 It's pretty intense price-wise, though likely incredibly relevant to those within the industry who like, specialise, and work with this sort of thing. Cheers, Chris

The Mycorrhizal Networks 2015 book is also out, so picked that up (can get it direct from Springer), and found Mycelium RUunning for £15 incl. postage. Christmas come early for me, considering the 5m diameter tape also arrived.

Managed to find both volumes of European Polypores for £85 incl. postage in very good condition, from Sweden.

Very interesting tree, and certainly great to see kretz in the flesh for the first time. In fact, I saw many interesting trees today. It really must be a pleasure (and a health and safety nightmare!) to manage mature and veteran trees on such a scale. Perhaps I overuse the word, but it's quite romantic in a manner of speaking to be able to just work alongside older trees and manage them into their ultimate death. That hard hat is a fashion nightmare. I believe that thing is still levitating. It may not even be a hat, but a bleached-white Leatiporus. Actually very much pumped to write this report - will get it done over the weekend, if all goes to plan. Got so many photos to sift through tonight.

Just a thank you to David et al. for accomodating me for a day to complete this exercise, and for the knowledge shared. Never seen so much fungi is one day, if I'm honest. More in that park than there is in the entire borough I manage with my colleagues!

Thanks for today, David (and the guys). Genuinely a wonderful day, and it was a pleasure to spend it in the company of a knowledgeable and welcoming team. That turkey oak is something else. Gorgeous tree. Really has a lot of character.

You're welcome. Was a nice one to write about, actually. Will sort out an 'index' for the second lot of 50 soon, so there are links to them all.

Watching a few videos by David Lonsdale for that very purpose.

...yeah, that one turned out to be an essay in itself.

15/12/15. Fact #100 (!!). We should all understand what a heart-rot is, some of the fungi that utilise heartwood as their energy source, and the type of heart-rots different fungi may cause (brown rot, white rot, soft rot), though how much do you know about modes of establishment - as in, how exactly do fungi colonise heartwood? It is first important to note that many of the heart-rotting fungi are very slow in their colonisation of their host. Colonisation and decay, such as with Fistulina hepatica on oak, may be very gradual. Because of this fact, and because we are learning more about fungi every single day, methods of colonisation are by no means conclusive, though general 'trends' can be observed. Typically, one would expect that, for heartwood to be colonised, then the heartwood must be exposed to ambient conditions - be this through trunk wounds induced by grazing, fire, and so on, or via wounds to the roots and branches that are substantial enough to possess heartwood. The below table shows how, on Quercus spp., different points of entry may be used by fungi, and the associated extent of decay associated with each point of entry. Taking the above into consideration, there are three points of entry that form two common themes. Heart-rotting fungi may enter at the 'top' (branches), at the 'middle' (trunk), or at the 'bottom' (roots), and these can be separated into two classes: top rot (entry via the crown) and butt rot (entry via the lower trunk and roots). In the case of top rot, decay will work its way down the structure, whereas in butt rot the decay will begin in the root collar region and propagate up into the butt. Usually, a species of fungus will fit into one of the categories. For example, Grifola frondosa and Pseudoinonotus dryadeus on oak will cause butt rot, whereas Laetiporus sulphureus and Stereum gausapatum will cause top rot. Therefore, it can be concluded that different fungi employ different strategies for successful colonisation. Expanding upon butt rots that may propagate through the soil, we can observe that species may utilise either soil-borne mycelium (migratory rhizomorphs and root-to-root contact), or even sporulate in the soil. From this, it can be deduced that, where colonisation is via root-to-root contact or rhizomorphic action, the same genotype is colonising the new host as has colonised the prior host(s). Heterobasidion annosum and Armillaria spp. are great examples of where a single genotype may infect many hosts (the former cannot grow rhizomorphs so relies upon root-to-root contact). Conversely, it appears that Phaeolus schweinitzii populations within a stand area may be far more diverse, given its means of propagation is via diospores. Panning-out and looking at colonisation strategy again as a whole, the distinction between the availability of exposed heartwood when comparing the root system to the crown structure is biased heavily in favour of the crown structure (given the aerial structure is more readily battered by biotic and abiotic mechanisms). Thus, it can be posited that where a fungus colonises determines how it colonises - be it exposed heartwood, active pathogenesis, or specialised opportunism. For active pathogenesis for instance, we can observe how Heterbasidion annosum and Armillaria spp. rely upon their own ability to colonise living roots through invasive forces, and how they may even opt to colonise already-stressed roots that are experiencing colonisation by other fungi, are residing within compacted soil, or are suffering from moisture stress. For top rots, we can safely assume that most - if not all - infections are via spores germinating on significant areas of exposed heartwood. For one, there is very little means of one Laetiporus sulphureus (for example only) getting close enough to another tree, and have sufficient innoculum potential, to infect in via active pathogenesis, so this method of colonisation is rendered defunct. Thus, colonisation via spores makes evolutionary sense, and this may make us question whether pruning a tree to an extent that heartwood is exposed is something to be desired. Of course, we cannot unequivocally state that a top rot will always colonise via exposed heartwood. A tree may not have such wounds and be in a location where colonisation is feasible. This is where specialised opportunism characteristically creeps in, after being latent in the discussion for a short while. Stereum guasapatum, for example, commonly establishes via such a method. It will enter the sapwood of branches and, from there, enter into the heartwood of the branch or enter into the heartwood of the adjoined main stem, where it will induce what is termed 'pipe rot'. Specialised opportunism doesn't stop there, however, as an even more clandestine strategy is adopted by Echinodontium tinctorium. This fungus can enter via stubs less then 1cm in diameter upon branches and, as the parent branch grows and begins to - in time - form heartwood, the fungus can begin its colonisation. It goes without saying however that the one limiting factor of heart-rotting fungi is their inability to colonise intact and functional sapwood. This means that fungus will be 'caged' into an area, though this doesn't mean they cannot colonise the heartwood present - which we know may take a very long time (this may even benefit their strategy of colonising heartwood, as by being slower at colonising, they don't use up their food source too quickly). Despite this, some heart-rotting fungi, such as Phellinus spp.., can breach into sapwood from heartwood via active pathogenesis. This can lead to the tree dying, once swathes of sapwood are destroyed (or the tree is girdled). More broadly, heart-rotters need to be able to breach intact sapwood to create sporophores (such as some Phellinus spp., where a progressively-thickening mycelial pad basically 'pushes' out the bark and ruptures it), unless they can fruit out of exposed areas of heartwood. Therefore, where a fungus enters via an exposed heartwood region, it may also use that site for its means of exit, and for species that enter via branch stubs, such as Porodaedalea pini and Echinodontium tinctorium, the branch stubs used for entry will act as the principal means of exit. Go out the door you entered by. A nice image to finish off, showing many possible routes of entry. A - large trunk wounds (exposed heartwood) B - dead branches lacking heartwood (specialised opportunists) C - in-tact branches containing heartwood where decay starts in sapwood (specialised opportunists) D - branchlets with (currently) no heartwood (specialised opportunism) E - buries branch stubs (specialised opportunists) F - rhizomorphic spread (active pathogenesis) G - root-to-root contact or grafting H - equivalent to 'C' but in roots (specialised opprtunists) I - soil-borne basidiospores Source: Rayner, A. & Boddy, L. (1988) Fungal Decomposition of Wood: Its Biology and Ecology. UK: John Wiley & Sons.

Not sure if any of you guys have read the new AA magazine, but it's got some right cracking articles this edition. Ted Green's and Jeremy Barrell's articles are great, and the one on Bialowezia NP is very interesting (I wish it were longer). Jeremy Barrell doesn't like highway middle managers!

I just realised we're in December. I've been putting down the month of November for all the posts during December, I think. Tragic! 14/12/15. Fact #99. Exactly how the rooting system of a tree will 'branch out' is species-dependent (as is it different between varieties of the same species), as is it dependent upon soil conditions, though it is generally accepted that roots will branch far more readily than the foliage crown will. And so we enter the realm of numbers... Kolesnikov, in his 1966 book Fruit Biology, found that apple seedlings could produce between five and seven orders of lateral roots during one growing season, of which third and fourth-order roots were most abundant. The same research also identified a one-year old Malus prunifolia to have 40,000 roots, with a total length of 230m. Extrapolating this out, it was estimated that a mature tree of the same species may have several million roots that, when laid out lengthways, may amount to several kilometres in distance. Further studies have also been undertaken on other species of tree, and it is evident that there is marked difference between species. In four-month old seedlings of Pinus taeda and Robinia pseudoacacia, 419 and over 7,000 roots were found respectively, of which total root length was 161cm and 32,500cm (again, respectively). Similarly, when a six-month old Pinus taeda were compared with an identically-aged Cornus florida, it was found that the former had 767 roots (amounting to 387cm total length) and the latter 2,657 roots (amounting to 5,144cm in length). The study also highlighted that, due to competition, forest-grown seedlings will have, on average, fewer roots than specimens of the same species grown in isolation. ...das ist numberwang! [ame=https://www.youtube.com/watch?v=wJs3Tsx-3Ak]nümberwang[/ame] Source: Head, G. (1973) Shedding of Roots. In Kozlowski, T. (ed.) Shedding of Plant Parts. USA: Academic Press.

I remember that being on the BBC a year or so ago. I hope studies are being done to some extent (whether to be published as peer-reviewed articles or just companies testing compounds), so it'll be interesting if anything comes out in the coming few years on the effects of garlic.

I don't know what the costs are, though I am sure Bartlett would. My concern with these sort of things, like as David mentioned, are the non-target impacts. What else are we nackering at the same time? Glynn Percival suggests perhaps a fair amount of other species in places, and in other instances not many, but rarely, if ever, can we get something that only impacts upon the thing we are looking to purge from existence.

13/11/15. Fact #98. Been a little busy these last few days with assignments, though here's an interestic little one I first heard about earlier this year at Barcham. When a horse chestnut is host (when is it not!?) to leaf miner (C. ohridella), injecting the tree with Emamectin benzoate, an insecticide, has shown to be nearly 100% effective after two seasons, and was done with full success in London during the Olympic Games 2012 preparations (trees were injected in place of being felled, and the leaf miner presence completely went away). Typically, only one injection is required no more than once every three years, in small dosages that are fast-acting. Ultimately, an integrated pest management (IPM) approach, including biochar application, Emamectin benzoate root flare injections, and application of Agri-Fos (or other Potassium phosphate fertiliser) can nullify HCLM presence, as well as having theraputic effects for the tree (such as reducing stress levels); this is critical as it has been found that HCLM causes hosts to lose 40%, year on year, of its energy reserves. It is not a cosmetic problem. Could this chemical therefore be utilised in the future more readily, or should be not be opting for chemical controls? Something worth considering. Sources: Burkhard, R., Binz, H., Roux, C., Brunner, M., Ruesch, O., & Wyss, P. (2015) Environmental fate of emamectin benzoate after tree micro injection of horse chestnut trees. Environmental Toxicology and Chemistry. 34 (2). p297-302. Percival, G., Banks, J., & Keary, I. (2012) Evaluation of organic, synthetic and physical insecticides for the control of horse chestnut leaf miner (Cameraria ohridella). Urban Forestry & Urban Greening. 11 (4). p426-431. Percival, G. & O'Callaghan, D. (2015) Pest and Disease Control [seminar]. Barcham. 1st July.

Surrounded on one side by woodland and grassland, and on the other by the edge of town. There are certainly not enough roadside trees, nor trees in gardens, though I am certainly better-off than most with regards to how 'tree-y' the local landscape is.

11/12/15. Fact #97. Juglans spp. will secrete a chemical called juglone, which impacts upon the growth of other constituent plant species of the rooting environment local to the walnut tree(s). This secretion of juglone is known as an allellopathic effect. In a study that examined sensitivity of juglone by 16 different species of plant seedling, it was concluded that all 16 species tested suffered negatively as a result of the juglone. Shoot elongation and dry weight mass accumulation were impacted in all seedlings, whilst seed germination rate and radicle extension growth were impacted in only 6 species and 11 species, respectively. The greater the concentration of the juglone, the more marked the impacts - to the point that seedling death would occur when juglone concentrations reached high levels. It was also determined that the impacts of allelopathy were greatest (adverse growth rate and other issues may manifest after only a few years) when young trees were located within the rooting environment of a mature walnut tree, and least impactful when seedlings grew up alongside walnut seedlings (where impacts may manifest only once the walnut trees reach a greater age - typically 12-25 years, according to a study of 41 different sites). It must be noted however that as the study only looked at visible impacts of juglone upon growth, there may be a period of many years prior where the impacts of juglone are apparent but simply not manifesting visually. Soil quality may also impact upon the efficacy of allellopathic chemicals, such as juglone. Where soils drain poorly, and are of generally poor condition, allellopathic effects are more significant and occur more rapidly. On well-drained soils, the effects of juglone may not even manifest at any point. Source: Rietveld, W. (1983) Allelopathic effects of juglone on germination and growth of several herbaceous and woody species. Journal of Chemical Ecology. 9 (2). p295-308.

Hah! fair shout.

Indeed! And there is no greater act of kidness than planting a tree in whose shade you will never be able to sit (I cannot remember where I read that from). It is the generations following who will benefit from the tree. Those lime tree paintings on the previous page are great, as well. That man was drawn to that tree for one reason or another - do you know why? In a field of trees, I wonder why that one was selected.

Fair shout - never seen that colouration (or lack of!) on laetiporus before. Learn something new every day! I didn't take a chunk out of it - literally pulled the car over to get some quick shots, so wasn't thinking about much other than getting a few photos. Thank you to all of you on this one. Next time I see something like this I won't rule out leatiporus based on the colouration of the bracket.

Hmm.. The bottom bit I can see being that, but the top bracket? I haven't seen chicken of the woods ever be so fan-shaped and adopt such a brilliant white appearance in the sun. Usually it's a dullened off-white when decaying.