Lapsed pollards...shade makes the situation even worse?

[Xerxses]

I have very little first hand experience of maintaining pollards especially lapsed ones. I have followed various threads about staged pruning and how to treat them.... But what if they are not pruned?

What happens?

What are the problems? I have been asked and can't really give definate answers?

 

Due to weak "new" branches they will collaps eventually? Is this true?

 

Due to the fast growing rate of the new growth, the annual rings are wide and therfore more prone to breakage? Is this true?

 

All trees that grow at a fast rate are weaker then if they were shaded and due to this grows slower? Is this true?

 

Any input and discussion appreciated!

[David Humphries]

It's simple really.

 

There aren't any ' definate' answers Tobias.

 

Too much shade will lead eventually to unsustained vigour & eventual death.

 

Too much newly given light (haloing) can & does scorch leading to probable death. (even thicker barked species, oak etc....)

 

Old lapsed pollards with large dynamic young growth does tend to end up snapping off from the Boling, (due to unsustainable weight & decay)

 

 

 

 

Reduction of height over time and cycle, is possibly the best & only way to return to a feasible pollard.

 

& the same with introducing more light in to the equation.

Little bit at a time if budget & oportunity allow.

 

 

 

 

.

[Xerxses]

It's simple really.

 

There aren't any ' definate' answers Tobias..

Well... I know, but would'nt it be nice if there were some short, simple and easy ones to pass on?

I'll ask a few "stupid" questions and state a few things just for the sake of diskussion...! So here goes;

 

"Too much shade will lead eventually to unsustained vigour & eventual death.."

Obviously it would depend on what species we are talking about. Willows and the like beeing the ones that would fail early as they are pioneertrees and cant tolerate shade, or? In your experience does beech tolerate heavy shading or will they decline fast?

Is there any good recomendations for different lapsed pollards according to the specie?

 

"Too much newly given light (haloing) can & does scorch leading to probable death. (even thicker barked species, oak etc....)."

Is this a problem with all species as they have been pollarded? Thinning of a forrest is normally not a problem if you are carefull (pines and beech beeing trees that doesent like sudden change in lightconditions)

 

"Old lapsed pollards with large dynamic young growth does tend to end up snapping off from the Boling, (due to unsustainable weight & decay)."

Is this due to fast growth and competiton for light? Why and when does it happen?

Is it due to lack of carbonhydrates and "spongy" wood with little ligninforming in the wood or is it wide annualrings and therefore lack of bending ability? Or is it just a question of leverage (Mattheck; height versus girth problem?)

 

 

 

 

"Reduction of height over time and cycle, is possibly the best & only way to return to a feasible pollard.."

How long a period? How much?

-Hit 'em hard and let 'em resprout, then give 'em a good slap on the head 5 years later?

Would you eventually bring them back to the original boling, or would you aim on a higher point where the cut would be smaller?

 

"& the same with introducing more light in to the equation.

Little bit at a time if budget & oportunity allow.."

 

So this would be the general advice? Slow and little bit at a time?

[Xerxses]

Is this how they do it at Burnham? Any experience from Ash and Oakpollards and how about coppicing, does the same rule apply? Taking every two or three stools and leave one for shade?

[Xerxses]

How about woodstrength? Is a shaded tree stronger cause of thin annual rings or is it stronger if its allowed to grow fast?

[morten]

New branches will break off easier since they are only attached to the trunk superficially (outer annual rings), whereas regular branches are attached all the way into the central annual rings.

 

Combined with the fast regrowth, their size and weight make them break off easily in high winds.

[David Humphries]

Tobias,

 

Helen Read has literally just sent me the final report on the City of Londons work on the Basque Pollard restoration project.

 

http://arbtalk.co.uk/forum/picture-forum/11489-study-tour-basque-region-trees.html

 

The report is far to big to post here & it's at work on the Pc.

 

When I'm back in the office next week I will..........

 

a/ ask Helen if it's Ok to send you a copy of the report before it gets published.

 

or

 

b/ find out where & when it's due to be released.

 

 

I'd imagine you would find it very interesting.

 

There's a summary version, which I will try and put here on a thread, once I've talked to Helen.

 

 

 

.

[Xerxses]

Too many questions?

 

I know most of the answers, but thought it would be interesting to hear others experience.... and share knowledge.

 

Looking forward to the report!

[sean freeman]

A relatively shortened version of the BB paper has been available on the ATF website for a bit..

http://frontpage.woodland-trust.org.uk/ancient-tree-forum/atfnews/images/Read%20QJF%20April%202010.pdf

[sean freeman]

Main paper...

http://www.cityoflondon.gov.uk/NR/rdonlyres/3560F960-F4D4-4F35-AE82-57B80D72816C/0/OS_BB_manageplan0510.pdf