daltontrees
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Everything posted by daltontrees
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Horrific, going to get me some Aspen. But you didn't say, is Aspen Benzene-free?
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How best to deal with this copper beech
daltontrees replied to Legohead's question in Homeowners Tree Advice Forum
PS I know this won't be poular view, but I'd buy that house and then get rid of the tree. Why? Who would live in the shade of a beech tree, it would be like living in a cave. You'd have the lights on all day. It would make the house unattractive to most buyers and the house would be a bargain. But my tree work costs me nothing. Actually what I would probably do is plant something smaller and more appropriate in teh garden towards the road, leave to for a coupke of years to establish and meantime reduce the beech once a year quite substantally and see if it could be kept as a garden bonsai with bearable shade implications.. -
How best to deal with this copper beech
daltontrees replied to Legohead's question in Homeowners Tree Advice Forum
If the tree's failure wasn't foreseeable, then what you say is correct. If it was foreseeable, then the tree owner is liable for damage outside his boundary. Since the potential purchaser has been told there is decay that could be further investigated, reliance on not being liable for offsite damage woild be a very poor decision. In plain language, the way I see the law is (and imagine th tree falls over after the house has been bought and moved into aand wrecks the neighbour's house). If the tree was knackered and you knew it, you're liable. If the tree was obviously knackered and you hadn't even checked it, you're liable. If the tree was knackered, you checked but only an expert would have known it, you're not liable. If the tree was knackered, you hadn't checked but only an expert would have known it, you're not liable. If the tree was knackered, you had checked and suspected it had hidden problems but did nothing more about it (like getting in an expert), you're liable. -
No. Good effort though. I think C.a and C.d subsp. a are synonyms, hopefully the system allows for established synonyms under different authorities, but if you know otherwise please let me know. #Anyway the answer is to do with the non-italicised part.
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Interesting, but if I read it right you need an iPad adn this blue thing that communicates with it by bluetooth over a range of 15m. That could get cumbersome in practice. Unless you could mount the blue thing on your head. That would leave hands free for the iPad. Might draw a few funny looks though. And/or cook your brain.
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Recent experience suggests that GPS can't betrusted even when the signal is 'aged'. Surveying last week I established a location in clearing, then watched for 5 minutes as the cursor location (stated by the machine as HDOP 0.8m) wandered off across the clearing, into the trees, back into the clearing, across it and out the other side.That was with the Trimble immobile on a tree stump. According to the base map which had a hypothetical development layout on it, the sub-metre position had travelled 25 metres.
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Ah but QTRA expresses relative damage or harm as a proportion of the value of a statistical life, does it not, and if so everything should be related to that standard and the term 'harm' is I would suggest (strictly speaking) inappropriate.
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Nope.Each tree either fails or ti doesn't. The sequence is irrelevant. If tree 1 fails and tree 2 fails and tree 4 fails and tree 7 fails etc. te probability of each is 1/2 and the probability of any 14 failures is 1/2 x 1/2 x 1/2 etc. 14 times, which is 0.000061. But since you were setting out initially to express the risk of this in 'language outside of probabilities', it would suffice to express it as freakishly bad luck. Like a coin toss coming up tails evey time 14 times in a row, it's unlikely but in practice and in theory it's possible.
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A bit late, but I am going to add Cedrus libani subsp. atlantica 'Glauca Pendula'. Can any clever-clogs say why this wouldn't be acceptable under the current convention? Longest variety name I have come across is Syringia vulgaris 'Andenken an Ludwig Spath'
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I have nothing further to say to QTRA about Monte Carlo simulations. They do little more meaningful than standard deviations can do, unless you assume (unintuitively, in my opinion) that risk is preceived on a linear scale.
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Ah well you and she will just have to wait and see what my view on that is. Hazard assessments in isolation are about as much use as, say, shoes without feet. And without something to walk on they're both irelevant. Think fuiguratively and you'll see what I mean.
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I have my concerns about the use of Monte Carlo simulations only for QTRA, it is the single biggest turn-off for me of the whole QTRA model. I told Mike what I thought about it at the Conference dinner, but after quite a few drinks maybe I didn't put the point as clearly as I thought I did. Come to think of it, he called me (with a grin) a cheeky b..... but took my point. Or so I thought.
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Thanks. Unfortunately the NASA threshold is 'harm' and th HSE one is 'death', so they are not quite compatible. But I shall have a look elsewhere to establish the reliability.
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Well, I,m afraid that I disagree with this, I think Matheny & Clark were way way ahead of the game on this, for reasons that I will be exploring in my article. The latest ISA manifestation seems to misundertsand them, and the outcome is the proabilistic mayhem that you have flagged up in this thread.
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Peer review can take a while, and it's out of my control. It'll come along in due course in one of the Journals.
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Yes that clarifies that there is more than one tree. However, isn't the risk of 14 of the trees failing and killing a child each is 1/2 to the power of 14 or 0.000061, following the multiplication theorem of probability?
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You've told us what's happening. A fancier explanation might be the behaviour of Homo sapiens manifesting itself. Is there a second question, like should we be doing something about it, and what? Or how did we let it come to this? Or is it inherently a bad thing? Pretty darned good if you're a chinaman living in Dubai called Patel.
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Good one! Books refer to these 'heels' as cups. Quite distinctive. Since Picea is pronounced Pie see a, the way to remember this is pull off a needle and if you can say 'I see a' heel or cup, it's 'Pie see a'. Other mnemonics may be available.
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Another question if I may? Are there equivalents in the USA and Australia of the ToR framework? And if not, do you consider it universal enough to be applicable there?
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Another thought, would analysis of the ISA system in numerical terms not benefit from a Monte Carlo simulation to better define the overlaps?
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Sorry, I don't follow this. Have 14 children been killed by one tree? Doesn't the risk arise from a hazard and the harm is done when a tree fails and then once failed that hazard cannot fail again?
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Sorry for delay in replying, I have been inordinately busy lately. Your original post makes it pretty clear what you would like to do. But it's still not clear why you want to do it. I mean, you are representing the commercial interests of QTRA Ltd., are you not? It wouldn't be the first time Arbtalk has been used for commercial interests, in a way that's partly what it's for, for people in the tree business to help one another. But in so doing the benefits are shared within the business. This research is generally a deserving area of work, and as far as I am concerned you are entitled to ask for people to chip in. I suspect you already have the answer. I sould also explain that I have been working on this issue for about 6 months, covering it as part of a bigger piece of work that at the time you posted last week I was tidying up for submission for peer review and publication. Since then I have been doing 2 big tree surveys and using these as an opportunity to thrash out some concepts in my head regarding quantification of tree risk. One piece of information had been missing, namely a copy of Matheny & Clark's 1994 book, which I got through the post last week. I am glad I waited for it, because the hazard rating it introduced remains the foundation of most if not all proprietary quantitative and qualitative tree risk assessment methods and I was missing some of the perspectives on this that required the whole book and not just the abstracts that I have been using for my draft.
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Your pictures are a wee bt vague, I am trying to imagine what you have seen... In the meantime here's a thought. There is a superficial similarity between rocks and trees in cross section. The rock formed from sediments. If you get a handful of dirt and shake it in a bottle then stand it still to stettle, in a few hours you will see that the largest particles (pebbles, coarse sand) settle out first, then fine sands and silts, finally clays. Some stuff will hardly settle out at all. This is what happens in nature, a blast of sediment comes into a lake or shallow sea from a storm in the mountains, and a layer of sediment going from coarse to fine forms. Next time another layer is laid on top of it. The layers can represent one year, as the bulk of sediments coming into the lake or shallow sea can be in spring with melt-water. The tree forms from vascular vessels and woody cells. In spring the tree comes out from dormancy, flushes its leaves and draws huge amounts of water up the stem for transpiration and photosynthesis. The ring-porous trees in particular develop very big xylem vessels for water transportation in the first couple of months of the growing year. Then the tree settles down for the rest of the year and puts on smaller vascular vessels. This accounts for the ring structure of wood. Trees and rocks therfore both have the same characteristics, each layer or year's growth starts with large vessels or partiles and grades into smaller particles or sells then stops for the year or season. Manys a time on the beach I have been stunned by the similarity between sedimenraty structures and wood structures. I will dig a bit deeper and see if I have a few photos in my collection to illustrate. Before I was a full-time tree-bore I was a part-time rock bore.
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It's still the middle of May. The Ash up here aren't even in leaf yet. C.f highly unlikely.
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I don't think it is a Spruce. It could be a young vigorous Abies alba. The growth all seems fresh and new and maybe disguising the more familiar identification chracteristics. Like cones, mature needles with white bands underneath and mature bark.
