Kveldssanger

The underside I did consider may have been that when looking at it, but doubled-up with a different fungus atop. If it is that (the top bracket), it's unlike any other desiccated one I have ever seen. If I am honest, I don't think it is chicken of the woods, but I do stand to be corrected.

09/12/15. Fact #96. The accumulation of toxic heavy metal ions within the soil, which may be brought about by acid rain, industrial pollution, or otherwise, is known to have negative impacts upon the ability for decomposers (fungi and insects) of an ecosystem to function properly. This leads to imbalances in nutrient cycling, litter decomposition, and productivity of the ecosystem, which in turn can impact upon vegetation life, and may lead to stresses developing that can increase in severity over the years. Source: Pennanen, T., Perkiömäki, J., Kiikkilä, O., Vanhala, P., Neuvonen, S., & Fritze, H. (1998) Prolonged, simulated acid rain and heavy metal deposition: separated and combined effects on forest soil microbial community structure. FEMS Microbiology Ecology. 27 (3). p291-300.

Evening, Spotted this today. I have seen this particular fungus a few times before, though have yet to identify it. Consulting literature, I am leaning towards Postia sp., particularly P. stiptica, though I need confirmation of this (as I may be entirely incorrect in my assumptions). Roger Phillips' book states it is mainly found on conifers, though this is a cherry. I make note of its intense whiteness, which is said to be a characteristic of this particular species according to this source. Images (mousewheel click to view in large size) - Fungi pictures Cheers.

Without question, you are right. What I'm trying to say is that human movement and consumption has played a role in the progression of chalara, in a sense that is 'artificial' - a pathogen would have typically not been able to hitch a ride on an ash sapling making its way swiftly across the North Sea from continental Europe, until we came along and decided to import ash from other countries. To play a role in something, watch the brown stuff hit the fan, and then go "nah I think we can just leave this one to sort itself out" is more than a little bit sketchy, in terms of behaviour, and therefore I consider humans having a role to play in reducing the impact of chalara. That is not to say 'mother nature' wouldn't do a good job, as with the Alaska oil spill, and the BP oil spill, the areas just left to their own devices typically fared better than where man went tin with more chemicals to clean up the oil spill they created. There is a time and a place to accept that nature will 'self-order', but when we have induced change from the natural order of things, we at least need to consider assisting with the regaining of order. As for scaring the public to help out, it's rather ironic really. Not many members of the public were aware of our massive importation of ash stock from abroad, nor the slight nonchalance about chalara when it was first found in Europe, so to then expect them to be burdened financially with 'helping out' could be seen as the antithesis of 'logic'. The industry, in part, created the situation, so the response should really be by those who fuelled the issue before it suddenly became 'big'. Donations have their place, but scaring people into giving away money is not the way to do it - we should not rely on donations to bail us out of mistakes. We should rely on foresight and critical thinking for that - you can't buy those skills. We saw the same with Dutch elm. It's almost like a repeat ad nauseum, with nothing ever changing substantially. We still import a lot of stuff to provide for a growing population with ever-increasing demands (that the public do, in all fairness, demand, in part), install phytosanitary measures, watch a pest come over, bemoan and lament the emergence of said pest, then carry on doing what was basically done anyway. It seems that the symptom is always tackled (the pest), not the cause (importation of goods, principally).

Yes and no. We tampered with the genetic quality of ash in the 70s and 80s when masses of woodlands were planted up - gentic provenance was poor, in many cases. Therefore, one could argue that we now need to step in to fix a problem we created (both by tampering with genetic qualities of ash, and hastening the spread of chalara). A hands-off approach, when we otherwise always have a hand-on approach to everything, doesn't make much sense. Yes we need to allow the ash to regenerate naturally, though that cannot be done by the ash alone. We continued importing stock from Germany and The Netherlands long after they suspected they had chalara, for example. Stupid, stupid, stupid. We cannot absolve ourselves of that mistake by saying "oh nature will fix itself". Well there wouldn't have been a problem if we didn't tamper with nature like that in the first place. Let us not also forget ash dieback isn't the only stress we have induced upon our ash. Pollution, landscape fragmentation, and otherwise, are further stressors. We also need to ensure that emerald ash borer doesn't make its way over here, else we are quite literally going to be screwed.

Same. That sort of stuff always leaves me in a state of awe. We're really just scraping the surface of how plant communicate, and what we're essentially seeing here is a peer-to-peer economy between plants. Take the following extract for example, with sources attached, from Simard (2009). "In a study examining carbon transfer in mixed Douglas-fir plantations, Simard et al. (1997) showed that summer shading of Douglas-fir increased its sink strength and net carbon gain from carbon- and nutrient-rich paper birch source trees. The amount Douglas-fir received in deep shade was equivalent to 10% of its total carbon budget, an amount comparable to carbon investments in seed production. In a later study, Philip (2006) showed that shifts in interspecific source–sink relations over the growing season reversed the direction of net transfer in spring and fall; that is, it occurred from Douglas-fir to leafless birch. She also found that the amount of two-way transfer increased over the growing season, when root and ECM fungus development were greatest (Philip, 2006), agreeing with an earlier study in maple forests by Lerat et al. (2002)" So basically: trees take ('borrow') resources - and return the favour - when their donors need resources back. Quite literally a community of trees. Sources: Lerat, S., Gauci, R., Catford, J.G., Vierheilig, H., Piche, Y., & Lapointe, L. (2002) 14C transfer between the spring ephemeral Erythronium americanum and sugar maple saplings via arbuscular mycorrhizal fungi in natural stands. Oecologia. 132, 181–187. Philip, L. (2006) The role of ectomycorrhizal fungi in carbon transfer within common mycorrhizal networks. PhD thesis, The University of British Columbia, Vancouver, BC, Canada. Simard, S. (2009) The foundational role of mycorrhizal networks in self-organization of interior Douglas-fir forests. Forest Ecology and Management. 258. S95-S107. Simard, S., Perry, D., Jones, M., Myrold, D., Durall, D., & Molina, R. (1997). Net transfer of carbon between ectomycorrhizal tree species in the field. Nature. 388. p579–582.

07/12/15. Fact #95. Found something cool, so there is a fact today. In a new study looking at the inter-connectedness of Pseudotsuga menziesii in an ectomycorrhizal sense, it was found that older trees had a discernible role in facilitating the growth of younger specimens via the shuttling of nutrients (sugars, etc), via the ectomycorrhizal network of, in this instance Rhizopogon vesiculosus and Rhizopogon vinicolor (more research is needed into links via other fungal species). The mycorrhizal network from these two species was found to, in one tree, provide links to 19 other trees of the same species - all within a 30m x 30m survey zone. The interesting thing about this, the study states, is not only that it adds serious weight to the concept of a forest being an inter-connected cohort of trees that form, as Shgio put it, one 'larger' tree, but also the fact that this research identified connections via only a select few ecotmycorrhizal species. When one considers that there are many species of ectomycorrhizal fungi within an ecosystem, the fact that there are also many different species of tree and plant within an ecosystem, and the fact that ectomycorrhizae may shuttle resources between different species at different times of the year and under different circumstances, a seriously complex ecological matrix is born, by where removing or stressing one tree (particularly a larger, older one) will have identifiable impacts upon trees connected to it. The study also shows that ectomycorrhizal species massively benefit from this relationship, as much as the trees do, as their diversity across large age ranges means that they always have a role to play and will never become obsolete, assuming the ecosystem remains healthy and functional as is currently. The below image, taken from the study paper, really drives the above points home. This is in the 30m x 30m zone surveyed. Now add in all other trees species, ectomycorrhizal species, and pan out to forest-level, and bask in the mental image produced. The intricacies of the natural world, and it's all going on right beneath our feet. Fascinating! Source: Beiler, K., Durall, D., Simard, S., Maxwell, S., & Kretzer, A. (2010) Architecture of the wood‐wide web: Rhizopogon spp. genets link multiple Douglas‐fir cohorts. New Phytologist. 185 (2). p543-553.

No fact today, but a load of videos courtesy of the Ancient Tree Forum. I don't recall seeing them on the site a few months ago, though it seems they were provided by Vetree, which ended in 2014 (so the videos may be one or two years old). Very informative, I must say. Veteran tree management | Ancient Tree Forum

Awesome. Thanks for the offer - shall PM you if things get dire!

Certainly happy to travel for this one. I'll drop you an email during the week and we can go from there. Many thanks.

06/12/15. Fact #94. Root crown excavation is a relatively contemporary method of treating landscape trees that are either in decline or are visibly dying, as a result of being distinctly below grade (either because they were planted too deeply, or because the soil profile has subsequently been raised). The process involves removing excess soil from the root plate region, be it by hand (trowel, spade, etc) or through mechanical means (air spades), and also undertaking remedial works to the root crown itself (if necessary) - this may involve removing potentially girdling roots, for example. In this study, eight tests at different sites (where trees were planted below grade) were conducted over a period of four years, to determine the impacts of root crown excavation on the health of the subject trees. Each study site had, on average, 40 trees, and the age of all trees across all sites was between 0.5-9 years - very much were all the trees still juveniles. Each site contained many specimens of an indivudal species, which differed between sites - oak, elm, maple (x2 sites), spruce, ash, and gleditsia species (x2 sites) featured within the study. At this point, all sites were separated into two equal groups - one control group (where no root crown excavation was undertaken), and one group where root crown excavation did occur (the 'study' group). In this study group, potential girdling roots were removed. For the excavation of the root crown area, compressed air was used, and saw soil removed to a radius of 18in from the base of the tree. Where soil was removed from the root plate to lower the grade of the soil profile, it was done to the point that the main lateral roots within the radius were exposed (slightly, upon their upper surface) to ambient conditions. Measurements were then subsequently made after 18 months following root crown excavation (and then again at intervals untl the four year period ended), and involved ascertaining foliar chlorophyll content, the rate of secondary thickening at 1.4m up the stem, the rate of primary elongation, the increase in specimen height, and the activity (and abundance) of pests associated with the tree species. Results suggested that there was no significant difference in the foliar chlorophyll content between the control and study group, nor was there any significant difference in growth rate, at four of the eight sites (oak, 2x gleditsia, spruce). On the other four sites, it was shown that the 'treated' trees did respond significantly as a result of the excavation works. On the sites where maple was the species studied, the trees exhibited reduced foliar chlorophyll content and reduced growth rates. It is thought that the removal of roots that may have developed into girdlers did not help, as such root severance may have induced moisture stress. On another site (where elm was studied), chlorophyll content of leaves improved and there was a huge surge in height growth on the individuals that were treated with root crown excavation. At the final site, where ash were studied, it was shown that the treated ash responded favourably and exhibited increased foliar chlorophyll content. It was thus suggested that the response to root crown excavation work was species-specific, though more work is needed, over a much longer period of time, and to a more diverse age range of trees, to ascertain exactly how different species respond to such treatments. In the period between this study and any long-term, comprehensive ones, trees planted (or existing) below grade should, at the very least, have the excess soil removed so to expose the main laterals to ambient conditions upon their upper surface. Caution should be exercised if the severing of future girdling roots on maples is being considered. Source: Rathjens, R. & Sydnor, D. (2009) Evaluating root crown excavation as a treatment for landscape trees. In Watson, G., Costello, L., Scharenbroch, B., & Gilman, E. (eds.) The Landscape Below Ground III. USA: International Society of Arboriculture.

Hi all, As part of my Lvl 4 with Treelife, I need to undertake a 'case study' on a tree, where the use of decay-detection equipment (PICUS, Resistograph, Thermal Imaging, etc) is required, and then conclusions be drawn as to what is next for the tree in question (continued inspections, reduction work, fell, etc). My question is thus: Is there anyone in the Essex / London area that has some of the newer tech', and is also willing to accomodate me for a morning / afternoon whilst the device is being used (for a justifiable reason - such as a tree shows some serious bulging around the butt), subsequently sharing the information with me (graphs, cross-sectional tomographs, etc), and allowing me to write a report on the results provided for my course? I am based in the Southend / Chelmsford area, though can obviously travel if needed. The office where I work does have an old resistograph, though frankly I am keen to try and observe some of the more modern equipment in use - such as the new PICUS, for example. Other LAs nearby either don't have the tech, or use the tech sparingly (or bring in contractors), and as I am limited with time for this (on-site inspections need to be done by the end of March) I am keen to get things done far in advance - it's much easier that way. Drop me a PM if you can help, or know someone who may be able to. Cheers, Chris

05/12/15. Fact #93. Most roots will grow within the first 50-75cm of soil as, below such levels, soil aeration progressively falls. As roots need to uptake oxygen in order for respiration to occur, such depths beyond 1m are typically less desirable; unless soils are very fine and sandy, or cracks within rock faces allow for a greater penetration depth of oxygen. For most species, when the oxygen levels falls below 10–15 % in the soil, root growth is inhibited – growth stops completely at 3–5%. Such conditions occur when air-spaces in the soil are replaced by more soil (compaction), water (flooding – particularly detrimental during the growing season and where flood waters are static and warm), or gases such as carbon dioxide, hydrogen sulphide, and methane (gas leaks are perhaps the principal driver, here). Sources: Crow, P. (2005) The influence of soils and species on tree root depth. Edinburgh: Forestry Commission. Davis, M. (2015) A Dendrologist's Handbook. UK: The Dendrologist. Shigo, A. (1986) A New Tree Biology. USA: Shigo and Trees Associates.

From a genetic standpoint, certainly. I would suggest a move away from ornamental species (more typically clonal) and a resultant move towards appropriately* genetically (and thus ecologically) diverse species (both intra- and inter-species). * local / justified provenance

Finished reading the report. Full of interesting observations and conclusions. Some charts were a little confusing and, infrequently, congested with too many lines that were difficult to discern from one another with ease, but most did a great job of presenting the data. It was interesting to note that 21% of all of London's trees are considered to be clonal varieties, based on the sample plots. That is a little concerning.

Some interesting charts from the above source:

04/12/15. Fact #92. Of the estimated 8,421,000 trees within London (constitutes Inner and Outer London), approximately 57% are privately-owned whilst 43% are publically-owned. Inner London has a total estimated tree population of 1,600,000, compared to Outer London's 6,800,000. Tree density stands at 53 per hectare (squared), which is lower than the national average, generated by similar surveys, of 58 per hectare. Tree cover within London is considered to be around 14%. Space to theoretically increase the tree population does exist, though as nearly 40% of London is currently of an impermeable surface (cement, tarmac, building, etc), and because of the large abundance of underground services, careful planning is required. At present, London has from between 3-6% of land classified as 'bare soil', so trees could be planted here without removing anything else, assuming there is space above- and below-ground. Source: Rogers, K., Sacre, K., Goodenough, J., & Doick, K. (2015) Valuing London's Urban Forest. UK: Treeconomics London.

Never good - hope you get the cash back. I know one contractor who got shafted out of a good few thousand quid by an organisation that decided they weren't going to pay him. It went to court in the end. Shameful, as with anyone who refuses to pay. Unless the service is dire and there is justification, pay.

03/12/15. Fact #91. Spurred on by the i-Tree report for London, I thought I'd start looking at both the report and the wider understood benefits trees provide in urban areas. In this case, we'll be looking at stormwater management. Both the crown and root system of the tree aid with the reduction in storm water accumulation, via interception of water from the foliage and crown structure above ground, and the rooting system below ground increasing soil-water infiltration rates (by up to 60 times in as little as two years after planting) by allowing water to flow down alongside channels created by root elongation and presence. By reducing the risk of storm water accumulation, not only is the risk of flooding lower, but surface pollutants are washed away at a more staggered pace, thereby reducing the likelihood of pollutant-rich storm water causing environmental problems downstream. The i-Tree Report for London in fact concluded that the 8.421m trees in London alleviate 3.4m cubic metres of stormwater every year, which amounts to a financial value of £2.8m. Sources: Bartens, J., Day, S., Harris, J., Dove, J., & Wynn, T. (2008) Can urban tree roots improve infiltration through compacted subsoils for stormwater management?. Journal of Environmental Quality. 37 (6). p2048-2057. Dover, J. (2015) Green Infrastructure: Incorporating plants and enhancing biodiversity in buildings and urban environments. UK: Routledge. NTSG. (2011) Common sense risk management of trees. UK: Forestry Commission. Rogers, K., Sacre, K., Goodenough, J., & Doick, K. (2015) Valuing London's Urban Forest. UK: Treeconomics London. Xiao, Q. & McPherson, E. (2002) Rainfall interception by Santa Monica's municipal urban forest. Urban Ecosystems. 6 (4). p291-302.

Indeed, I hope people read it and absorb the information. If there are any spares, drop me a line David. Cheers.

Question - will this be published for purchase as a paperback copy? Would certainly buy one if it does get printed.

Thanks for this, David. Shall read this tonight and tomorrow.

I am indeed at Harlow. A lovely setting for the course. Sticking with NTSG... 01/12/15. Fact #90. When a tree within a park area is identified to be in a poor state, and the area beneath it is considered a target zone of at least some significance, then the first question asked is not "what works must be done to the tree?" but "can the target be moved?". Assuming the target can be moved, NTSG provide an array of options that can be drawn from. These are: - deter informal cark parking beneath the tree (also reduces root damage via compaction, in particular) - re-locate facilities such as play equipment, benches, commemorative plaques, etc, out of the reach of the tree if it ever fell or shed limbs - re-direct paths, if legally practicable - design paths that can be mowed so that they run through long meadow grass, drawing foot traffic away from the target area - have assembly points and other structures built for 'congregations' out of the target zone Altneratively, access can be full-out deterred by: - planting thorny scrub - creating log piles around the tree - allow grass to grow long - leave brash around the base of the tree - create exclusion zones (temporary or permanent - weather-dependent) - alter the area's overall land use designation (from pasture to hay meadow, for example) Source: NTSG. (2011) Common sense risk management of trees. UK: Forestry Commission.

Absolutely. I am doing mine with TreeLife. Yourself?

I am doing the lvl 4 but not got to trees & the law yet! We're on mechanics at present. Yes, you are right. As it says in the NTSG guidance, the media will over-play tree deaths and injuries as it's so rare. The shock factor, so to speak. The M25 is nasty - had to drive back that way last week and I don't envy drivers who use it daily. Some lorry drivers are so unecessarily aggressive with their driving.