BatiArb

This is an unfortunate fact from a literary research point of view but if you are interested in some exploratory observations yourself then there is an exciting opportunity to learn more. That opportunity is something that certainly maintains my interest in arboriculture, there is just so much more to learn and there is really no need to worry about your educational background because practical arborists are in a position to literally show academic researchers what is actually going on…… The advance of arboricultural knowledge in the hands of practical arborists and all we have to do is find a way of communicating our observations and ideas. This forum and others like it are where it is at and where ideas are communicated that will change the perception of trees in the future……. Keep it up guys….. :beerchug:

Very good point, and perhaps impossible to tell definitively without some investment in scientific research on how ivy reacts to different growing conditions and therefore whether it is able to grow proportionally better in the current warmer climate with high levels of C02 . Any volunteers……? However, it would be extremely useful to have some observational data from people working out in the field observing trees on a day in day out basis, because there are some very simple questions that we do not know the answers to. Like does ivy grow all year round? Having done a little digging around the subject there is very little in the way of useful information that is of practical help to the arborists responsible for managing trees. So I think it is time we did something about it. The sort of information we need can be gathered by anyone with a tape measure and camera, with the common sense to make consistent records.

I have observed Collybia fusipes in a similar location to that which you describe, and on a number of different oak trees in varying states of maturity. The common factor appears to be associated with stressed roots as a result of either damage through severance, water logging or compaction. Considering also that the other species of Collybia are all saproxylic, that is live of dead wood, then my feeling is that its presence at the base of these trees is a symptom of root issues. Considering the location of this tree, and the target area you describe, then I would suggest that you undertake an investigation of the tree’s buttresses using an AirSpade and see how much root damage the tree has sustained.

Now I know ivy can be a contentious issue and is frequently the subject of heated debates, which historically have been relatively evenly matched, with the outcome really dependant on the location and management context of the tree concerned. However, in recent years I have been asked to consider the influence of climate change on the growth rate and competitive success of ivy. There are a number of hypotheses that have been raised, which include: a) Longer growing seasons for ivy allow it to take advantage of trees that have lost their leaves in autumn. This means that the ivy can gain the upper hand and could possible smother the crown of even a healthy tree. b) The increased CO2 in the atmosphere is beneficial to the ivy and is increasing its growth rate and enabling it to compete successfully with healthy trees that would have historically maintained the upper hand. c) Trees are suffering increased attacks from introduced pests and diseases, at the same time as being compromised by low water levels and as a result ivy is able to smother more trees. These are just three possible scenarios that could be happening, but I have had a number of reports of situations where people have observed ivy smothering trees and hedgerows. Now the issue is that the reports are not necessarily an unusual thing, particularly in the autumn and winter when the presence of ivy becomes more obvious, so what we need is some form of historical evidence to substantiate whether there is an issue here or not. That is the reason for this thread, because I would like to know your thoughts on the issue, with consideration to the three scenarios described above, and others that you may have. We also need to start a few trials to observe the growth of ivy and the health of trees it is growing up, and this really means getting out there with the camera and taking pictures of trees with ivy. Then getting the tape measure out and keeping a record of the respective growth rates of tree and ivy The following things need to be considered: 1. tree species 2. length of time it is in leaf, from full canopy in spring to leaf loss in autumn 3. health and growth rate of the tree 4. species of ivy (although best to keep to Hedera helix for the moment) 5. length of growing season for the ivy, from when it first starts growing in the spring, to when the annual extension growth stops at the onset of winter. 6. health and growth rate of the ivy Again these are just a few key points that we need to consider, and of these I think 5 is one of the most significant, because I would be interested to know how much of our ivy actually continues to grow through out our mild winters and at what rate.

Perhaps I should clarify a point here.. I am not saying that Meripilus is totally innocent, I just want more arborists to consider it as a symptom that may or may not be associated with a stability of health issue that required recommendations that could include felling or reduction work. Meripilus like any other organism is an opportunist and will take advantage of a situation, so where root damage occurs within the lateral root system the fungus will be able to exploit the area, and we all know how susceptible beech trees are to surface root damage. Particularly when they are adjacent to paths, roads or bridleways. In such cases a further root investigation should be carried out by someone familiar with the interaction of decay fungi and tree roots, to make an informed decision as to how progressive the situation is and whether tree stability has become compromised. Root damage does not necessarily have to be physical to allow the advance of decay. Compaction can cause dysfunction within tree roots that allows the ingress of oxygen into the system and creates the conditions within the woody root system in which decay fungi can grow. Again these are complex issues and we should be clear about the diversity of contributing factors involved and not persist with generalisations that serve only to confuse the situation.

Yes, research is on going, but we will also never know everything, so are you going to continue condemning trees on that basis......waiting until we have all the answers…. The point I am trying to make is that by blaming the obvious, healthy trees are being felled needlessly….. is that what tree care is all about ….. I think not …… The presence of fruiting bodies such as Meripilus and Grifola are symptoms of a natural process, so our job as arborists is to determine whether the symptom is associated with something that could cause a health and safety issue or is detrimental to tree health and therefore its longevity. I used to work as a climbing arborist running a contracting business serving domestic clients, so I am familiar with the situations you describe. I also thing that clients value the opportunity to make informed decisions based on choices that we can offer them. As such I think we demonstrate our care of trees by explaining that fungi are part of the natural survival strategy of trees and are integral part of their ability to survive for hundreds of years. However, under some circumstances in combination with other factors they can sometimes contribute to tree stability issues that we need to be concerned about. Such situations need, and deserve, further investigation so we do not make rash (unprofessional) decisions biased on limited information. Although I agree that not all client will be prepared to commission us to undertake that investigation and that is their prerogative as the tree owner. Our job is to offer them the opportunity and provide them with a balanced informed opinion based on the best, most up to date information possible.

Your example is classic, because the symptom of crown thinning and dieback that you describe is not actually associated with the presence of Meripilus, and just confirms the fact that there was something else wrong with the tree. Unfortunately your subsequent decision to fell every other tree you have observed with Meripilus is characteristic of the naivety of arboriculture as a whole. Likewise the sweeping judgment that beech as a species cannot survive climate change. Such poorly substantiated generalizations should be avoided, because they only serve to cultivate ignorance and do nothing for the expansion of knowledge or understanding……. There is nothing wrong with not being able to find an answer to a problem, but you are selling yourself short by not even trying and throwing away the evidence so no one else can work it out……. Arboriculture is about tree care isn’t it? So why do we spend so much time identifying reasons to take trees down, rather than spending a little more time to find constructive and informed solutions to why trees can be retained?

The cooler areas that are visible up the trunk of this tree are where there are thinner sections in the functional shell or residual wall around the central core of seasoned (dysfunctional) wood. Yes you are right it would be possible to observe a split occurring in this way, but that is not the case with this particular tree.

That is certainly the case and I think we need a far more considered approach to such things, because we are all too quick to jump to conclusions on the first sign of a fruiting body. To be frank, as professionals educated in tree care we really should know better……. As I suggested in my postings on the Grifola thread (http://arbtalk.co.uk/forum/showthread.php?p=71269#post71269) it is all to easy to just investigate one aspect of what are frequently very complex tree issues, with many processes a natural part of the arboreal ecology that we should not be considering to be a problem at all. Meripilus is a classic example of this because it has attracted a very bad name for itself and I believe has been falsely blamed for root plate failures. In a very similar way to Grifola, Meripilus is associated with the decomposition of the dysfunctional root system of mature trees. Although unlike Grifola it does not appear to have the capacity to produce fruiting bodies from deep decay, well below the soil surface. As such the decay is likely to be very close to where the fruiting bodies are observed, which is a useful characteristic to observe. The file I have attached this time provides an example of a mature beech tree which was observed with Meripilus fruiting bodies around its buttresses for a number of years. However, the tree pictured in the photographs has not been seen with any brackets around its base for over ten years. The thermal image picked up a column of seasoned (dysfunctional) wood up the centre of the trunk, which is characteristic of trees that have been subject to some form of basal decay. However, the buttresses can be seen to be healthy and the tree is surviving very well, with no apparent detrimental affects from the history of Meripilus. It is also worth considering at this point that the vigorous growth of the fibrous root system around the basis of this tree may be in part due to the fact that the decay of the old root system has released nutrients into the soil that are now enhancing the trees growth. This is nature demonstrating how true recycling works…… Thermal of Beech with history of M.giganteus c.pdf

Now looking at that tree it appears that the presence of Grifola is likely to be a symptom of other issues that look like they could be more to do with the poor growing environment with extensive surface compaction and lack of organic soil horizon. Which is consistent with a general issue I observed when I visited Highgate woods a year or so back. The interesting thing about Grifola is that it has the ability to produce fruiting bodies that are associated with very deep decay, well below the soil surface, so the presence of the brackets you observe around the tree are not necessarily directly associated with decay in the immediate vicinity. This is where the mycelial tuber comes in, because it allows the fungus to generate the fruiting body on the surface of the soil which is well above the area of decay. I think this is a classic example of how we can be distracted by the most obvious symptom and overlook the root of the problem (please excuse the pun). We have a desire to find simple answers to what are actually very complex issues that can rarely be resolved by a one off action or treatment. Again I would stress the point that we are observing the symptoms expressed by an evolving process within an ecosystem that is adapted to change over decades and hundreds of years. We create problems for trees because our lives are considerably shorter and we expect change and effect to occur over a much shorter timeframe. Meanwhile we inflict change on our environment, as individuals and as a population, at a rate which presents challenges for the organisms that we live with. This is particularly true of trees and this is one of the most significant issues we have to deal with as arborists. Getting back to your tree in Highgate Woods, I know this is a very well used bit of woodland in a residential area, and the human pressures on the site are considerable. I would suggest that you do not get distracted by the presence of the Grifola on this one tree, because the bigger issue here is one that will be affecting almost all the trees in the wood. However, I do agree that you are in a predicament where the presence of the Grifola does place you in a position were action is now implied by default so it has forced your hand to some respects. I would therefore suggest that you undertake a sympathetic reduction to bring the canopy below that of adjacent trees and the broader woodland. Basically undertaking as little as you can, so that reasonable actions have been taken to manage the situation responsibly, while also continuing to consider the implications of the wider issues of the trees growing environment. The rest really comes down the overall risk management policy of the site and how you balance the responsibilities of public health and safety against the value of the woodland as a multifaceted resource significant for its ecological and environmental sustainability. Good luck, and if you have the budget I am not that far away..... Regards, Andrew

That’s great, file is on its way to you. It was an interesting exploration into the rooting environment of this tree and as you will see from the photographs, at times, it was almost a case of arboriculture meets archaeology. Well at least in the methodology used by Marcus to excavate around the fungal fruiting podium, or what we called the mycelial ‘tuber’. (I on the other hand went in like a typical arb determined to play with his toys, so I took care of the soil around the buttresses with the AirSpade.) An extension to the series of photographs covering the investigation is the series of drawings I have attached below, these are an illustrative example of how the root of a mature tree such as an oak can actually become stronger through its partnership with the fungi that is decaying it. Yes I know that implies some form of acknowledgement or communication between the two organisms, but who are we to say that this isn’t possible. Again baring in mind that the progression illustrated below occurs over decades and the complete process could take a century or more in an oak tree, this is something that I have observed on a number of trees at different stages of the cycle. This is also something that may only really occur at the crossover between the trunk and the main root system, in the section we call the buttresses. This is very well defined within the oak tree that is the subject of the investigation for Grifola. The buttresses subdivide and diversify into smaller lateral roots almost immediately below ground level, and the buttresses on this tree were well advanced on the cycle, which was made possible by the presence of Grifola. The subdivision of the lateral roots from the buttresses in this way is something that I now consider characteristic of mature oak trees like this one, and have also observed on many other trees of different species. Now the point with the progression illustrated below is that the tree ends up with a structure that is far stronger than it started with, and in a form that could not have been achieved if the fungus had not decayed and effectively removed the old dysfunctional section of root. The other characteristic that should be observed in this tree and others of a similar age/maturity is the flair of the buttresses, which increases the structural footprint of the tree, spreading its load over a wider area of ground. In doing this it appears to reduce the load expressed onto the lateral root system and this is where the idea of the traffic cone analogy becomes most apparent. Again this is a feature I have observed on numerous trees of different species, although it appears most common on species such as Oak, Beech and Maple. Regards, Andrew Root BiomechanicalOptimisation.pdf Optimisation.pdf

Does not sound bad to me, I would question if it was even worth reducing. I also would not have chosen to drill such a tree. Grifola presents a root decay progressing to the base of the trunk, which is not something that can be accurately assessed by sticking a drill into the tree. Not to mention the potential for causing more damage and actually enhancing the progress of the decay into areas where it would not actually have been able to advance to. I believe drilling should be a last resort to confirm findings of non invasive assessment methods that indicate advanced decay that appears to limit management recommendations to either heavy reduction or felling. In such circumstances the decision is likely to be when the tree is removed rather than if. Marcus and I have undertaken a number of root investigations looking at Grifola and it appears to be a deep root decay that affects the dysfunctional remnants of the taproot and lower root system no longer used by the mature tree as a means of support. I believe that Grifola on oak performs a similar function to Meripilus on beech trees, but is much less invasive when it comes to progressing into the lateral root system. In fact it appears rarely on lateral roots and almost entirely confined to the dysfunctional centre of the trunk base and old root system. I have a photographic report of a detailed investigation that Marcus and I completed on an oak with fruiting appearing adjacent to two buttresses on opposite sides of the tree. However, it is too big to post on ArbTalk, so please e-mail me direct on [email protected] and I will send it to you as a pdf (please not it is over 5 meg is size due to the number of photographs) Following this investigation we were not inclined to recommend any work to the tree, even though it is growing in an open location and exposed to lateral wind loads accumulated across open fields. This is just another example of why we need to broaden our scope of understanding and appreciation for how fungi and trees work together in a positive partnership that can prolong the stable life expectancy of many trees. In such circumstance the removal of living foliage can actually create problems where there were originally a natural balance within a dynamic ecosystem evolving over the long lifespan of the tree. We are all to frequently too quick to condemn trees based on a moment in time that is a fraction of their lifetime. In human terms, we would not condemn someone for having a bad day or even being laid up with the flue for a week or so. The same timeframe in tree terms can be several years. It is essential that we respect the slow living processes of trees that evolve over decades and involve a diversity of cohorts that exist in harmony with them !

I've done my fare share of Land Rover bashing as well you know:

Fertilising mature trees is a total waste of time, money and effort. Artificially changing the nutrient balance of soils by using fertilisers creates more problems than it solves, because it all happens too fast. Mychorizal inoculations of mature trees are also a waste of time, because the tree could not have survived to maturity without having good associations with mychorizal fungi. The only effective 'treatment' is to remove grass out to the drip line, de-compact the soil (with an AirSpade), which gets the oxygen back in, and then incorporate a good composed mulch to replace the organic horizon that is an essential part of the trees growing environment. However, even adding mulch should be carefully considered with reference to the trees age and stage maturity. Any remedial work should be undertaken with full consideration to the long life span of trees and with respect for the natural time scales involved. I have attached more information on the various things to consider about mulch applications. Using Organic Mulch 0807-2pg.pdf

The presence of Meripilus at the base of a beech tree is not a reason to fell it !!!!!!!!!!!!!! My investigations of tree root systems and particularly those of beech have illustrated how little we know about them and more to the point the information available in books is totally misleading. Meripilus is actually an essential part of beech tree ecology and integral to its survival strategy. Yes it can become an issue when it gets into the lateral root system, but this is usually as a result of other root damage or soil compaction that has injured or killed roots that have then become available to be decayed by Meripilus. Where Meripilus is found at the base of a beech tree the decision to fell or even reduce the tree should not be made without undertaking a root investigation to determine where the fungus is living. In mature trees the structural bias of growth within the buttresses means that there is no longer a functional path for carbohydrates to feed and support the lower layers of the root system and the remnants of the trees ‘tap’ root. During its establishing years the tree maintains the lower root system, but in maturity a greater emphasis appears to be placed on the surface roots that then spread out to form a flair at the base of the trunk similar to that found on traffic cones. When the lower root system is no longer supported by the tree and is starved of carbohydrates it begins to dry out and progressively decayed by fungi such as Meripilus. As the wood is decayed nutrients are released back into the soil, where a fibrous root mass is growing from the surface. The tree is now able to effectively recycle itself, but only because the fungi are there to assist it in the process. The growth of the tree’s root system is totally different from the crown above ground level and its structural form bares no relationship, with a far greater proportion of young roots being produced on a cyclic basis. We have found significant concentrations of fibrous root growth at the base of trees and under the buttresses, particularly in association with decay fungi. The idea that a trees root system continually grows bigger and bigger out away from the trunk in a similar way to the crown in the air above, is a totally misconception and nothing like what actually occurs. Trees could not survive as long as they do without their close co-evolutionary relationship with decay fungi that are an integral part of their ecology. ConeTree.pdf Root Investigation CaseStudy C.pdf

For those interested in learning more or the opportunity of training in the use of Thermal Imaging camera technology, that will enable you to undertake the survey work yourself, this can be arranged in a number of ways: 1. Thermal Imaging Awareness Seminars are being arranged to provide the background information necessary to understand how a Thermal Images Survey is undertaken. The aim of these seminars is to provide the knowledge necessary to interpret Thermal Image Assessment Reports. The seminars are presented over half a day and are charged at £35.00 +VAT per person, and include a presentations followed by a question and answer session. 2. Training to undertake survey work as an Image Capture Technician having completed a two day course in camera use and survey techniques, using thermal imaging technology. The two day course is charged at £750.00 +VAT with accommodation arranged as required at extra cost. 3. Consultant level training to become licensed to use the Tree Thermal Matrix Software (TTMS) requires a minimum level of arboricultural qualification and practical experience before attending an intensive two day course followed by a period of mentoring to guide the candidate through the process of image analysis and interpretation of results. Consultant level training cost from £1,500 +VAT with accommodations arranged as required at extra cost. All seminars and courses are arranged based on numbers of interested candidates and can be booked by calling 0845 658 1400 ThermoEcology Email.pdf

The attached case study will offer an illustration of how the assessment methodology can be used practively to evaluate the condition of tree populations rather than just selecting the obvious individuals as we currently do with traditional decay detection devises. Remember Thermal Imaging is not simply a decay detection tool, because it enables us to consider tree physiology to assess the functionality of the tree first, and then consider the implications of the presence of decay, or other forms of dysfunction. Thermo Full Case Study Beach Road West .pdf

Again this provides more detail, but I am sure will also raise questions so please keep them coming..... Thermal Imaging How it Works .pdf

I am a little busy at the moment so will respond in more detail later, but through the attached article might provide some with a bit of background. Regards, Andrew ThermalRevolution.pdf