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tree-fancier123

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Everything posted by tree-fancier123

  1. maybe some of these links still live, have to register to download http://opeforum.com/threads/husqvarna-workshop-manuals.997/
  2. when I was 17 I remember buying a clapped out Fiesta and someone giving me a spare engine free, I did the job in a day with a chain hoist and a Haynes manual, never worked on a car before. These days the availability of service manuals, Ford, Iveco, Stihl etc has saved me some money. Sure I would know the underlying principles if I was time served, but if service manuals have the data and sufficient instructions to effect a repair then why not? I expect you could read enough to do a kidney transplant almost as well as a someone who has been to medical school. Good money in kidneys if you don't ask questions about how they got it.
  3. the trackers have helped to recover a lot of stolen plant, but I imagine many thieves are spending hours and hours thinking about this problem. Even if a tracker could be in the most cunning places, e.g sump pan, false bottom hydraulic oil tank etc, presumably it can be detected by some form of scanner, and blocked by an available jammer type. Of course not every thief will buy into the technology to defeat trackers. one side could be jacked on axle stand and wheel taken to job or home, then the thieves get into the habit of taking a spare wheel with them. A way out would be a box to tick at the general election - death to all thieves
  4. Concealed tracker in steel box welded into the frame possibly, there are animals on earth that look human. Maybe a night thief would even use a gas axe if he found a tracker.
  5. Are you just making conversation, or genuinely interested? results as per search e.g. Evolutionary biology Why are so many trees hollow? Graeme D. Ruxton Published:01 November 2014https://doi.org/10.1098/rsbl.2014.0555 Abstract In many living trees, much of the interior of the trunk can be rotten or even hollowed out. Previously, this has been suggested to be adaptive, with microbial or animal consumption of interior wood producing a rain of nutrients to the soil beneath the tree that allows recycling of those nutrients into new growth via the trees roots. Here I propose an alternative (non-exclusive) explanation: such loss of wood comes at very little cost to the tree and so investment in costly chemical defence of this wood is not economic. I discuss how this theory can be tested empirically. Many trees have a hollow or otherwise rotten core to their main trunk. For example, surveys of savannah woodland in Australia have found hollow cores (a phenomenon called piping) in 66–89% of trees of different species; on average, hollow cores extended to 50% of the total diameter [1–3]. A study in the Amazonian rainforest found 37% of trees from a broad range of species to be piped [4]. The most relevant hypothesis to explain this phenomenon is due to the renowned ecologist Daniel H. Janzen, who in 1976 published a paper entitled ‘Why tropical trees have rotten cores’ [5]. He hypothesized that ‘the rotten core is often an adaptive trait … A rotten core is a site of animal nests, animal defecation, and microbial metabolism that should result in a steady fertilization of the soil under the base of the tree. … Hollow cores are expected more frequently in nutrient poor sites … In short, the hollow core becomes a clever use of an otherwise useless piece of wood.’ Mutualistic interactions between microbes and plants are well known in other contexts, most obviously in the rhizosphere. Although it seems logically plausible, empirical support for the predictions of this hypothesis have been lacking. There may be low return of nitrogen to a living plant from termite activity within its trunk, with much of the nitrogen harvested from the consumption of the wood of a living tree being lost through predation and nuptial flights and as a result of heavy rains [6]. Further, any nutrients that are released into the soil are more likely to be captured by the shallower roots of the herbaceous understorey that compete with larger deeper-rooted canopy trees [7]. One key study found that in nutrient-poor Australian woodlands, growth and survival were lower in piped trees than size-matched unpiped trees growing in the same plot [8]. A follow-up study found that for one species of Eucalyptus, growth rate was independent of the extent of piping in trees of a particular total trunk diameter, whereas in the other study species growth decreased with extent of piping [9]. Here I offer an alternative (non-exclusive) hypothesis. In contrast to Janzen's hypothesis, I suggest that the tree gains no advantage from a rotten core, but rather (provided the rottenness is not too extensive) pays a very small price (in terms of reduced structural integrity) for allowing the central wood to rot. Furthermore, this cost can be lower than the metabolic costs required to chemically protect the central part of the trunk. So like Janzen's hypothesis, my hypothesis suggests that the prevalence of rotten cores can be understood in terms of selection pressures. But my hypothesis is very different in suggesting that there is no selective benefit from a rotten core (in terms of freeing up nutrients for recycling by the tree's roots), but that it is often not economical to chemically defend the central part of the trunk; and rotten cores emerge as an epi-phenonenon of this judicious lack of investment. Chemical defences against both microbial and animal damage to tissues are widespread across plants and can often involve very substantial metabolic expenditure. Hence, it may not be economical for a plant to protect all its tissue equally, and I will argue that the interior of tree trunks will often not be well defended. As a tree grows, so the trunk must thicken to carry the increased weight; such thickening involves the formation of new sapwood around the circumference of the trunk. Sapwood acts not only structurally but also to transport water from roots to leaves and as a repository for nutrients. However, sapwood is metabolically active and the maintenance of such tissue has been estimated as costing 5–13% of annual net energy gain through photosynthesis [10]. For this reason, many trees convert their innermost wood from sapwood to heartwood. Heartwood is metabolically inactive, plays no role in nutrient storage or water transport and offers no structural advantage over sapwood [11]. The attraction of heartwood is that it is dead and incurs no recurrent metabolic costs. Although some chemical defences may be laid down at the time of heartwood formation, the lack of metabolism in this wood means that such defences cannot be replenished when they decay, or be ramped up in response to specific attack. Thus, there may be metabolic savings a tree can obtain by avoiding investing heavily in the chemical defence of wood in the interior of the trunk. Given that this interior is often heartwood, the primary cost to this strategy is likely to be structural weakness as a result of decay or hollowing of this wood; below I will argue that this cost can be very low. As a simplification, the trunk of a tree can be considered as a cantilevered cylinder. As such, the greatest tensile and compressive stresses occur towards the surface and the interior contributes relatively little to structural strength [12]. A survey of previous research of the effects of trunk hollowing on the structural failure of trees found strong agreement across studies, involving a broad range of different species and broad range of tree sizes, that there was a critical amount of hollowing above which structural failure was considerably more likely [13]. This critical point occurs when the radius of the inner hollow region is approximately 70% of the total radius of the trunk. Hollowness less than this critical amount involves very little cost in reduced structural stability. This 70% critical value is broadly used in the management of trees, and in particular is a very widely used criterion for the removal of trees considered to be structurally at risk [14], although its theoretical basis is an area of still-active discussion [15]. In conclusion, I agree with Janzen that the widespread occurrence of hollow trees demands explanation. I also agree that an evolutionary approach can help generate hypotheses that might explain this phenomenon. Janzen offered one such explanation in terms of recycling of nutrients; here I offer what I believe is a more generally applicable alternative or complementary hypothesis: that the central wood of trees is allowed to decay because the costs of chemically defending it are not justified by the small reduction in structural stability that is likely to occur. This hypothesis is empirically testable. I predict a greater investment in chemical protection of wood against destruction in exposed and windy environments where structural stability will be more at a premium, and differential investment in chemical protection across the circumference of trees, with the outer portion being much more strongly protected than the inner. There is evidence that chemical protection of heartwood can vary according to local conditions, being affected by thinning during silviculture [16], but that same study found no evidence of consistent variation in defensive investment with heartwood age. It might also be valuable to explore extent of hollowing in large lateral branches as well as the central trunk of suitable species. Horizontal branches will often experience greater tensile and compressive stresses than an upright trunk of similar thickness, and might be predicted to be particularly strongly protected against decay. We might also predict that trees should avoid any hollowing of the trunk in the vicinity of large lateral branches. A lateral branch causes stresses to be imposed on the trunk, and if there is hollowing of the trunk near the branch then stresses will be concentrated on the outer wall and potential for local buckling increases relative to a situation where a solid trunk allows spreading of those stresses across the cross-section of the trunk (see [17] for further discussion). This illustrates that there will be a complex suite of selection pressures impinging on the design of tree trunks (and all other plant structures [18]). Furthermore, as Janzen's theory suggests a benefit to the plant from heartwood consumption, his theory would predict that plants should be selected to make this wood more accessible and/or attractive to decomposers. By contrast, if any such traits are otherwise costly then they should not be selected if the mechanism proposed here operates. It may also be illuminating to examine the diversity of bacterial and fungal communities in decaying central wood and contrast this with those in rotting wood associated with damage, to explore if there are functional differences in the different assemblages. Naturally hollow trees are very unusual, but do occur in the Neotropical pioneer species of the genus Cecropia, where internodes are either hollow or filled with pith—depending on the species. These species are fast-growing, relatively short-lived gap colonizers in tropical forests. They are characterized by having a relatively small number of slender branches at the top of the trunk carrying sparse leaf cover. Thus, the central trunk does not have to bear the same loads as those of more robust and more branched trees. Accordingly, the trunk is essentially columnar (like bamboo stems) rather than the more traditional tapered shape created by thickening at the bottom of the trunk over time. Cecropia does show, however, that naturally hollow trees are possible, but in most cases the complex of selection pressures on tree trunk design seem not to have led to this solution, although the sometimes extensive occurrence of microbially driven hollowing mentioned at the start of this article perhaps suggests that the costs of hollowing may often not be high. But we require more empirical exploration of hollowing, and I very much hope this article encourages and focusses such investigation. Acknowledgement This manuscript benefited from perceptive and constructive reviewing from Hanns-Christof Spatz and two anonymous referees. Footnotes © 2014 The Author(s) Published by the Royal Society. All rights reserved.
  6. I did read the Makita is a bit heavier than a 365, but had no idea either the Makita or Dolmar badge were electronic carbs? If they are electronic carbs I don't see that as a plus for the occasional user. You see plenty of old saws up for sale year 2002 etc, Do you think many Mtronics will last 20 years in the cold damp air of a shed?. Won't be much choice soon, other than refurbs way things are going. What a life with a view like that, would drive me mad
  7. Yeah gaff out there on a traditional flipline on side ds would be a bit of a slide. Good spiking and nice traverse too, skillz
  8. My sister got really bad swearing and had to explain it doesn't really make the conversation more exciting. I think for men working together it sometimes adds to the sense of camaraderie to say something like 'don't be a cant all yer loif'
  9. I may buy just a Teufelberger loop and ring, plus another ring and a maillon to try to modify my flipline like that - a poor mans version. The Buckingham system looks as good as having a choked main line for grabbing the tree in the event of a fall.
  10. It is something new. A flipline with improvement to help catch if you gaff out, already assembled. Occaisional users like me always gaff out. Maybe not needed by someone who can spike a pole blindfold. Must be easier spiking with than a multi-saver
  11. ah yes, the safety is another topic - my 441 has a strip of green stripey insulating tape on it, whevever I pick the saw up and think 'why is that tape on there?' I remember I put it on there to remind me of the day I was logging up a trunk and the bar nose came up so quick I only just stopped it from hitting my face, they always kill a few each year
  12. interesting you put the power of the Makita between a 460 and 660, at £550 they seem a bargain in comparison. I agree it would make more sense on a longer bar, as a saw just for ringing up
  13. the op says he has access to 20 to 30 inch pine and ash, surely it's best to have more than 50cc for ringing up those stems?
  14. crikey - enough horsepower there to cut down a whole rainforest
  15. I thought Stere also made a sensible suggestion (below). Putting the Husky 365 and Makita EA7900P45E side by side (the specs are similar, the Makita is 200g heavier, 8cc more displacement and slightly (0.9kW) more powerful). I would prefer the Husky as spares would be easier . The best google prices for both are £550 on 18 inch, some of these internet stores though I would be wary of. Radmore, FRJ etc established forestry suppliers won't be a problem Personally would use my 441 for ringing up 20 to 30 inch dia as op states. I don't use Aspen, just start, open tank, tip out and rev till it stops to store. Been doing that with it since 2011, never had to put a carb kit in it.
  16. Ok you dont like my mutilation pruning spec, but your 10 year fell - are you saying dont worry re his wife's safety concerns, or do you think there is reason now to justify the expense of an arboricultural report addressing the likelihood of damage to people or property within the next decade while the replacements are growing?
  17. I know I'll never make a proper arborist, but at least the less knowledgeable home owners will hire a cowboy gardener like me
  18. definitely good advice, in the autumn if either of them grow fungal brackets they are firewood looks like you've got space to plant some other bits and bobs, start growing replacements a bit further out perhaps
  19. Down south - so unfortunately it won't be me up there! Later on this evening I'm sure anyone nearby with a rope and harness will be on here after your readies
  20. I would love to spend a day in such a beautiful spot, if anyone gets to take a saw to them, it will be a nice job to go to hackers for hire
  21. what happens with insurance if they end up damaging the house?
  22. had a few days of high winds in the south, anyway was just asked about saving a conifer - its maybe 14ft high cypress type thing, blown about 20deg off vertical on Sunday, no rootplate up. I tied it using customers rope to a nearby arbor at the concrete base. There is a breezeblock wall about 3ft behind the tree and I said to customer on a nicer day it could be tied back with eyebolts. I now think this was silly as eyebolts likely to come out. The wall could be drilled through and I could weld up some bar with an eye on, but in a gale would the tree pull the wall down? Can tirfor and ground anchor to upright the tree before attempting to guy it somehow, but is it use the wall or try something else in the ground?

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