Ash die-back (again).

[Trailoftears]

Apologies if this has been covered before.As a general landscaper/manager of several rural properties,our local district is awash with dying/diseased Ash populations.Whilst the external symptoms are all too painfully obvious.What I'd like to understand better is from a safe felling point of view is how it progresses re: the heartwood with regards in particular for how long do they maintain live tissue in the felling hinge before they become unpredictable to fell.I'm thinking-and urging customers,that once the individual is obviously doomed its better to get on with it asap.But I have no evidence to back that up frankly.

[maybelateron]

I don't think you can apply any set timescale/formula to this, but I understand you asking. I have felled trees that looked ok/largely ok and found the hinge area was weak/rotten with no external signs; flip side I have felled trees where the crown looks really tired bit the lower trunk is fine. The only solution in my opinion is the look at the overall risk assessment - drop zone area targets/risk of branch falling out and hitting saw operator etc. If in any doubt walk away or seek advice, unless you have a good mewp and can pick bits off it. Every case is different. Definitely agree with advising owners not to delay - over the next few years there will be plenty of cases where through ignorance or lack of funds owners have ignored the problem and made it become a more expensive solution.

[Stubby]

And try to avoid banging wedges in .

[Mark Bolam]

Pretty much nailed it two posts in to my mind fellas!

[slack ma girdle]

There was a lot of concern about weakened fiber strength of dying Ash a few years ago. Having felled alot of dead and dying now the following are the main points of concern.

The tops die back quick which makes climbing  the smaller limbs dangerous. But the larger limbs take much longer to become unsafe , providing that the wood is still mostly white.

The biggest risk when felling is from branches being flung back at you as the falling tree brushes past adjacent trees .

I have had no issues with loss of hinge fiber strength,  including jacking over heavily leaning trees.

If it's an 'iffy' tree , then it becomes a two man operation with comms, one watching the crown whilst the other cuts.

I have not had any issues with banging in wedges and dislodging dead branches .

[peds]

Aside from being dangerous to climb, the brittle tips provide a pretty handy early diagnostic tool. Knock the suspect tree over, and if it explodes everywhere it has dieback and needs to be felled. If it remains fairly intact, it is healthy and can be put back up. 

[Trailoftears]

Where I am-west Wales,it seems to be racing thru valley bottoms/riverbanks more quickly than some of the elevated heights.Also,looking at grand old matriachs at say 300 yrs +,you can see its there,but not hugely noticeable to the layman possibly.But,young striplings of say 35 yr+ look shocking and are getting hammered really fast.I'm really concerned where big uns overlook clients drives and try to explain it only takes 1 10" major branch falling 20/30 ft to crush their car/kill them.Also I manage 800 mtres of an old railway line-shut down via the beeching cuts back in the day,which borders a country lane/cycle track.Whilst the ash are relative youngsters and fairly straight grown trees,it becomes obvious the whole length is doomed.Tragic really,one of those valuable wildlife corridors.There deffo seems to be a 'head in the sand attitude' with most of my clients.Leaving aside the tragedy of the landscape implications,it strikes me these trees will cause accidents, kill,maim people over the next 10 odd years.

[Trailoftears]

Thanks@slack ma girdle.

Thats vaguely encouraging,also thats a really good point about the danger of brush/past danger of falling branches in a densely populated area-just like the ex railway line I'm involved with.