daltontrees

I shall have a bedtime browse of Roberts Jackson & Smith. If I unearth (pun not intended) anything I'll share it here.

I expect pellets have a very high surface area to volumen ration compared to logs, allowing rapid drying and possibly escape of moisture during burning before it has to be boiled off. All good for calorific value.

David, do you know whether this process is giverned by any tropisms or is the curtailment of underside growth largely (or wholly) because of the steady increase in loading on the underside as the tree grows and sways, crushing or inhibiting the cambium?

Yeah, what he said!

Not quite. The higher the moisture content the lower the calorific value. The higher the holding temperature, the higher the calorific value. The two things are related insofar as driving off misture takes up energy that would otherwise be given off as dry heat. The colder and wetter you start, the more energy is wasted.

Could be Pleurotus dryinus.

Third looks to have gills, so not Dryad's Saddle, possibly Pleurotus ostreatus

Any chance of a picture next time you see it? I have never seen it on Sycamore and whereas I don't doubt you I would like to know what it looks like.

Ahh, another nail in the coffin of my Asterid theory, Willow is a Rosid.

It is also possible very reliably to link the calorific value to the moisture content. The amount of energy required per unit to take water in the wood from room temperature to 100 deg C and then vapourise it is fixed, see latent heat capacities. Oddly, it means that the calorific value of wood changes with the temperature it is held at.

Here's what I use, and I am certain that I derived it from a reliable source. Newly planted Not fully established and capable of being transplanted or easily replaced Young Establishing, usually with good vigour Early mature Established, usually vigorous and increasing in height Mature Fully established around half their species’ life expectancy, generally good vigour and achieving full height potential but crown still spreading Late mature Moderate vigour, no additional height expected and growth rate slowing Over-mature Fully mature, in last quarter of life expectancy, vigour decreasing But I would suggest you don't just copy it or anyone elses' definitions. Life stage is linked to vigour, potential for further upward growth, further outward growth, the onset of fruiting, the annual number of leaf flushes, degrees of susceptible ripewood or heartwood, step change in annual increments, ability to withstyand and recover from pruning etc. so whatever you choose as definitions I would suggest should be useful to inform the decisions that you arte about to make to serve the purpose of the survey. Or you can just do what everyone else does, mostly involving box-ticking for BS5837 surveys. Knowing is useful, but understanding is by far the greatest prize. Hows about you let us know how you get on in the assessment?

Seriously, my touchpad has reset itself recently so that if you brush it with your palm while typing, it can highlight a whole page of text and delete it irrecoverably in about 1 millisecond. Laptop nearly took flying lessons today... Ahhh the joys of Windows 8 an all the fleas that live in its hair.

I'll try to pin down the defnitive source for this tomorrow. It has always bothered me this very question but I formulated a reliable answer last year. If I can only find where I put it...

I just typed a long and knowledgeable reply, but my computer decided to delete it and I can't be bothered looking everything up again

Yes it seems to be not quite a loophole but a valid soft alternative to deal with a TPO application by making it a felling application. When the new Scottish Regulations were being drafted about 4 years ago, wisely or unwisely I pointed it out to Parliament but as with most things that sound to them like criticism they just ignored it. So, we have the same soft option up here. I expect if it became a serious problem and was being abused something would be done about it. In the OP's case, I think forced replanting of self-seeders would be ludicrous.

This was what I meant by there being no general answer. Large self-seeders in a Group TPO could be lawfully covered by CA status, and probably are if a safe persumption is needed.

.... and after basically getting on with what we have all been doing for years.

I am puzzled too, because it all seems to be coverd already by HSE guidance. Maybe not pulled together in a single tree work docoment, but it's all already there.

Much as I felt after the first reading, I am struggling (and I mean struggling internally between not wanting people to get hurt and wanting to get on with getting the job done) to see who will be grabbed by the document.

As long as you know that asking nicely will greatly help your chances of good quality answers. If you want to develop a meaningful online personality on Arbtalk, politesse is effective. But then, I am over 30 and politesse these days seems to count for nothing except engaging the attention of old-timers like me. I have just spent about 5 minute giving your question my undivided attention. An answer that covers most situations you describe is fairly easy, but an answer that covers every situation you describe is complex beyond stating here. So I am gong to suggest some general principles, but don't hold me to them being valid to every situation. Firstly, there is a general exemption for felling small trees about 3 inches diameter. 4 inches if it is beng done to thin and improve growth. Secondly, if you have a TPO in Conservation Area the amenity importance of the trees has already been decided. In most senses you can ignore the CA status and concentrate on the TPO status. Thirdly, group TPos include self-seeders. I recall that Area TPOs and indiviual tree TPOs are there to deal with the amenity provided by trees rather than the collective amenity of woodlands or groups of trees where the individuality of each constituent trees is not crucial. Personally I'd be taking the initial view that thinning or removal of small self-seeders within a groupTPO is exempt from regulation, but it always helps to tell the Council that before you rev up... the Council wil get the calls and will be on your side if they know the context

First posting, eh?

A quick bump up... Has anyone looked at this and if they did what did they think? Does anyone think we need a Code of Practice and would they use it? Anyone going to reply directly to AA? I am just curious but a bit alarmed at the lack of comment so far, despite lots of views. Anyone...?

Tgat is the answer. Low pressure by spreading the load over a large surface area odf wheels or even better tracks. SNH may be able to advise informally of machinery used in contracts for them in sensitive boglands. And perhaps an avalanche beacon

Trees of speical interest are loosely defined under a number of headings namely Ancient or Aged, Veteran, Heritage, Notable and Champion. The website says - "A national register would help owners recognise the value and importance of special trees on their land." Yeah fair enough, but only for trees that aren't already in TPOs, Conservation Areas or under managment of someone who already knows of the tree's special interest. "By encouraging owners to seek professional advice in how best to look after them, it could also influence a change in management to safeguard their future." OK, that's for all of the above trees, minus the ones where the owner doesn't care or can't afford professinal advice. "We would also like owners of trees on a national register to have priority for funding to help with their care." Gosh, is there funding for caring for trees? "But the most important reason for a register is to celebrate these incredible and much-loved natural treasures." Celebrating them I expect is done to encourage visits to them, all well and good if there is legal and physical access to them. I just wonder how many people (who don't already visit trees rather obsessively) would break out the Register on Sunday morning, identify a tree and then go and visit it with the family. I'd like to see a register if it were easy to put together and maintain, but it does seem to be aimed at very marginal gains (special interest trees accessible, not currently protected or known about and in the hands of someone receptive to their celebration, and not already described elsewhere in easy-to-use publications). How many such trees are there?

I suppose the analogy should include a squadron of planes leaving for each airport from each airport and as soon as a squadron hits bad weather one flies straight through to see how bad it is while the rest break off left and right to see how far round it is. I think I've taken that as far as I can, so I will stop before it gets ridiculous.