daltontrees

LAZZzzzzz......

The descending climber would be accelerating, which is taking soem of the force that otherwise gravitational acceleeration would take. So if you descend and accel;erate downwards at 2m/s/s the effective gravitational acceleration is reduced from 10 to 8 m/s/s, reducing the effective load. The potential energy released is absorbed in the crotch and the hitch, manifesting itself as heat and/or mechanical damage. Reductio ad absurdum: if you cut the hitch like Adam did to dolly, the acceleration of dolly equals gravitational acceleration, and the load on the curtain rail is (10 - 10) x dolly's weight. This will equal zero, there is no longer any load on the curtain rail or the rope.

And that, my Arbfriends, is how to kill a thread!

The problem is, the guy's application was refused originally on the grounds of 'unsustainable location', so working round the tree is not the whole answer to his problem.

Uh oh, looks like saome basic physics is needed here. Don't run away, it's fairly easy. You need only one equation. F=ma. Force equals mass times acceleration. When you are hanging on a single line the force on the branch equals your mass (and the mass of teh rope and the harness etc.) times the acceleration which if you are static is the gravitational acceleration. it is about 9.8 m/s/s. Call it 10. 100kg x 10 m/s/s = 1000 Newtons (the unit of force). Or 1kN. If you think about it, this is why gear rated to say 30kN can hold 3 tonnes or 3000kg. F = m a. So in the example, the rope is resisting all of this force, so the load on it is 1000N. every action has an equal and opposite reaction. One of Newton's laws of dynamics. But if you pull up on the single line to go up the ways, and you accelerate at 2 m/s/s, you are adding that much to the acceleration of gravity, so the load becomes 100kg x 12 m/s/s = 1200 Newtons. The load on the rope therefore depends on how fast you go up, and is only greater than the static load while you accelerate upwards. It might not be surprising to know then that if you start to descend, the load on the rope decreases. Using a doubled rope is a little more complicated. When static, the load on teh branch is still 1000N, but the load on each half of the rope is 500N. As you ascend, the load on each side is increased by half the additional total load. If you were accelerating upward at 2 m/s/s, the additional load on each side of the rope is equivalent to 1 m/s/s which means each side is loaded 10 + 1 m/s/s = 11 m/s/s times half the deadwweight. Using f=ma again, the load is therefore 11 x 500kg = 600N. With ropes of standard rating 3kN or 3000N, neither SRT nor DdRT will come anywher near breaking strain. To do that you would need to (using our F=ma in reverse now) accelerate at a = F/m = 3000/100 = 30 m/s/s. That is, your upward speed would need to increase by 30 metres per second per second. After the first second you would have to be travelling at 30 metres per second. Now I don't care how fast SRT is, that aint going to happen unless you're being hoisted by a medieval battle trebuchet. The modest DdRT man would by comparison have to be pulling through 60 metres of rope a second and be body thrusting like Beyonce on speed.

No no no. You pull 2 foot through. The rope shortens by 1 foot on one side of the crotch and 1 foot on the other side of the crotch. To go up a foot you have to shorten both sides of the pulley/crotch by a foot. To do that you needs to shorten the whole rope by 2 feet.

DdRT is definitely a 2:1 system. Again it's one of teh advantages of it because when bodythrusting you shove yourself up a foot and pull 2 foot of rope through. You gain a foot for 2 foot of rope pulled through.

You need have looked no further than Arbtalk's fungi directory Ganoderma pfeifferi - Bees wax bracket - David Humphries’s Fungi Directory - Arbtalk.co.uk | Discussion Forum for Arborists I'm not saying it's G. pfeifferi. It may well be lucidum. That's on the directory too.

You can see annual growth rings on these brackets, they seem to be perennial.

The branch/fork/cambium saver in DdRT is the pulley! The friction in it is quite useful in bodythrusting, buying you tiem to advance your friction hitch. But the same friction is the thing that makes it hard work.

That's a little harsh. Tony's post contained a clickable link to Wikipedia's definition of countercoultire. Something like 'A counterculture (also written counter-culture) is a subculture whose values and norms of behavior differ substantially from those of mainstream society, often in opposition to mainstream cultural mores.' It goes on to say 'A countercultural movement expresses the ethos and aspirations of a specific population during a well-defined era. When oppositional forces reach critical mass, countercultures can trigger dramatic cultural changes.' Makes a SRT counterculture sound rather noble ands progressive. Now that's wortt a Teeshirt. Anyone got a suggestion of a suitable motto? I don't know Tony but I know of him here on Arbtalk as someone whose choice of words is first class. Please don't let your passion for SRT prevent you seeing that his comments were pretty objective and apposite.

Did he say you were outcasts? I missed that bit. Fair enough about muscle groups. A hard day's body thrusting knocks the heck out of me. It's fairly simple for me. I use STR sometimes to get into a tree, quite often to get out of a tree and rarely within a tree. It's just part of a repertoire of tricks and techniques. I don't intend to get a bumper sticker and tee shirt to say which camp I'm in. I kind of expected someone to suggest that if SRT is quicker a business will be more profitable or more competitive, meaning food on the SRTers table while the prussikers starve. Now that's a selection pressure!

I don't think you understood what he said. What would the selection pressure on climbers to use SRTWP be?

I'd largely go along with that. Please don't get your hopes up though, the Council must have due regard to objections but if it then cracks on and confirms the TPO, there is no statutory right of appeal. You could complain to teh ombudsman if you think you have been unfairly treated or you could in theory and with very deep pockets raise a judicial review. Focus on the question of whether the tree provides amenity to the wider public. That's the real test. I think the Council has probably satisfied the expediency test already.

You could even if you were using a base anchor.

It's not a course, it's a chapter. In a book called the Traffic Signs Manual. It's the 8th chapter. The chapter is devoted to the design and operation of signage and work sytems where the road is to be obstructed temporarily. It is there to protect workforce and to manage traffic safely and efficiently around the obstruction. It is for the employer to ensure that the health and safety of his employees is taken care of and that road users are not put at risk or unduly inconvenienced. Now in theory an employer can delegate responsibility of the design and operation of the signage to employees. But he cannot do so without ensuring that the employee is competent to do the design and to make sure the signage is set up on site properly. He can't just pass the buck. So if you work full time for someone there should be a clear understanding in place about who is responsible and that the responsible person has the right training. The way this operates within the organisation should be set out in the health & safety policy and should work its way through to the site-specific risk assessment and method statement if the contract requires one. If your employer is requiring you to design or set up signage (i.e. the typical cones and signs around the chipper, truck and worksite) and didn't specify in your employment contract that you had to hav ethe relevant training, it is your employers responsibility either to design and set it up himself or to provide you with the training to do so. It's the law, there is no contracting out of it. Insurers will run for cover if you have not complied with it. If it's not done right people can get hurt or killed. So the question, should you 'have' chaper 8, I suppose means should you have been trained in the correct design and operation of signage for temporary traffic managment around a work site in accordance with the Traffic Signs Manual? Someone in the organisation, the person responsible for the design and operation, must. Thereafter it is a case of what your employment contract says. If it says nothing about it, in my view if you are being asked to set up cones and signage regularly you should have been trained through your employer. I hope that's clear and helpful. Welcome to Arbtalk, by the way. Be smart and be safe and you may have a long and enjoyable career in arb ahead of you. An understanding of Chapter 8 is one of many many things you will pick up along the way. Arb is mored with health & safety, and there are good reasons for that.

It is for the Council alone to decide whether it is 'expedient' to make a TPO. One of the usual justifications is tha there is a real or perceived threat to the tree. Looks like the Council was right. And/or you have been out-manoeuvred. It doesn't really matter whether the Council TPOd because of a neighbour suggestion or not. What is jumping out at me is this. If the Council is satisfied with its reasons for refusing your previous planning application, there should be no reason to make the TPO. But if the Council perceives that you perceive (think about it) that removal of the tree would improve your chances of getting permission next time, it can make the TPO. It doesn't really matter whether that perception is justified or not. There is only one thing that matters. The TPO must be on the basis that the protection of the tree is in the interests of the amenity of the area. Is it a good specimen? Is it visible from public areas? Has the TPO just been served and are you therefore within the timescale for objecting?

|I think the source of confusion is really obvious. If your rope is over a branch and down to your frictiobn hitch/device, that's a doublED rope. And of course a single rope. If you are climbing and cutting you should always have 2 separate attachments, often 2 separate ropes. That's doublE ropes. Those ropes can of course be doublED. It'd qurte right to say that it is safer to cut from double ropes than from a single rope. But when the single rope is doublED, cut either side and you are mince. There was a thread about the terminology for SRT a few months or a year ago. Personally I gave upon it because no-one seemed to care that the current terminology was ambiguous and therefore potentially dangerous. Fun video, though. I guess if dolly had had her CS38 she wouldn't have put a loop of the makeshift harness around her neck.

That helps, if ythat is thw Commission's interpreatation of the law. I would be cautious, though, the Forestryu Act says in a roundabout way that a legal right of access does not include the general right to roam under the Countryside Act

Too big for P.sylvestris, pretty extreme for P. nigra. Try P. radiata (Monterey Pine).

Sorry, I disagree for the reasons I have just posted. Common land is just one example of where the land might be public open space.

In the Forestry Act, “public open space” means land laid out as a public garden or used ... for the purpose of public recreation, or land being a disused burial ground. It looks like the land doesn't neeed to be open in the sense of having wide open spaces but open in the sense of unrestricted access. I would think for the exemption to apply, the land would need to be devoted to public recreation as its sole or main purpose, not just used for say occasional dog walking as a purpose ancillary to its main purpose or with public recreation tolerated. Indicators of purpose might be signage, lack of locked gates, byelaws, planning policies in the Local Plan and so forth. Herein therefore may lie the answer to the OP question. If the land is devoted to public recreation, no felling license is required. I hope this helps. There is one caveat. You quote - 'Felling fruit trees, or trees growing in a garden, orchard, churchyard or designated public open space (eg. under the Commons Act 1899).'. However, the Act doesn't say that. It says - 'the felling of fruit trees or trees standing or growing on land comprised in an orchard, garden, churchyard or public open space'. Either yoiu have misquoted or paraphrased, or my legislation reference is out of date. Please correct me if I am wrong.

I helped out on the Glasgow version of this. Interesting work and a worthwhile project. Took me 3 months, 4 days a week. Gotta know your shrub idents.

If you'd just wanted to know that, maybe you should have started a poll? I was just trying to be helpful. So to answer your new questions a. I've never been asked and b. I've never been asked. Over and out.

An interesting question! The Act says tha the exemption (i.e. under 5 cube a quarter) applies to "trees on land in [a person's] occupation or occupied by a tenant of [a person]" It would seem that the exemption applies to the person, not to the land. But by extension, the land is the land in the control of the person. The Forestry Commission website and leaflets do not seem to elaborate on this, referring only to 'your property' which merely underlines the emphasis on ownership/control rather than defined estates or holdings. All a bit hopeless if you own a series of scattered plantations.