Crown thinning verses Crown Reduction

[Tony Croft aka hamadryad]

how about the difference in wind sail and loading between a proper thinning (done mostly on the outer third to two thirds of the canopy) to a crown reduction? that would be great data to see!

 

jp

 

Oh dear, how many more times do we need to re apply the "common sense" that short and fat= GOOD tall and thin= BAD!

[swinny]

As a total newbie, can someone point me in the direction of some good photo's? maybe before after? for the correct thinning etc Cheers all

[Mark Cattell]

Hi andy2,

 

I don't think there's a vesus point to be made as they both serve different purpose and you end up with a different result. You can do a list of pros and cons for each of the techniques, but you can't compare them side-by-side as it were.

 

Agree totally,

 

If Its a light issue from the client then species will play a major key to which one to advise....

[Tony Croft aka hamadryad]

As a total newbie, can someone point me in the direction of some good photo's? maybe before after? for the correct thinning etc Cheers all

 

hamas big pruning reduction thread for starters!

 

dont know about thins in other threads but a good look about will find em!

[Paul Barton]

Different pruning specs for different trees!

 

I wouldn't specify a crown thin on a leggy ash in an urban environment - a crown reduction is ideal there to reduce wind sail and loading on long limbs.

 

Personally I would only specify a thin if a tree's crown was oddly congested or full of vigorous re-growth from previous pruning. And I would normally suggest a thin due to light issues rather than to lessen wind-sail.

 

I think crown thins can often be misunderstood as removing 'excess growth' - as if the tree grew all these branches by accident because is has made a mistake!

[Bundle 2]

Hi andy2,

 

I don't think there's a vesus point to be made as they both serve different purpose and you end up with a different result. You can do a list of pros and cons for each of the techniques, but you can't compare them side-by-side as it were.

 

Whilst this is true....I am personally not a fan of thinning, regardless of species virtually. In fact, pruning needs be considered from the view of habit. Decurrent an excurrent requiring a different approach.

Excurrent HOW to Prune Trees, Excurrent

Decurrent Decurrent - Wikipedia, the free encyclopedia

Here are documents for those wishing to read further into tree mechanics, loading and mass damping. ( Its not light reading but stick with it..Ken James has done quite a bit in this field.)

Apart from anything else, thinning tends to result in the tree putting down new wood only locally. This results in a loss of taper to limbs and an increased end loading. None of this is condusive of a healthy plant and cannot often be justified imo. The more you understand what you are doing, the better able you are to make the right decision and advise a measured recommendation re: tree management. My advice is DONT DO IT

Engineering in Arboriculture.pdf

Mass Damping. K.James.pdf

Dynamic loading of Trees.pdf

[Tony Croft aka hamadryad]

Whilst this is true....I am personally not a fan of thinning, regardless of species virtually. In fact, pruning needs be considered from the view of habit. Decurrent an excurrent requiring a different approach.

Excurrent HOW to Prune Trees, Excurrent

Decurrent Decurrent - Wikipedia, the free encyclopedia

Here are documents for those wishing to read further into tree mechanics, loading and mass damping. ( Its not light reading but stick with it..Ken James has done quite a bit in this field.)

Apart from anything else, thinning tends to result in the tree putting down new wood only locally. This results in a loss of taper to limbs and an increased end loading. None of this is condusive of a healthy plant and cannot often be justified imo. The more you understand what you are doing, the better able you are to make the right decision and advise a measured recommendation re: tree management. My advice is DONT DO IT

 

good post Bundle, got a few lessons to learn from you:thumbup1:

[arbogrunt]

Always an interesting debate!. I think it depends of a number of factors, species of tree, habit of tree, location, objective of pruning, previous history of pruning to tree and most importantly of all....how the work is carried out!. A tree that has been 'thinned to reduce' that has been done sensitively and achieves balance through the crown will look pretty good for a couple of years after the work has been carried out. A tree that has had a crown reduction with heading cuts applied (and usually with too much of the crown removed), will look pretty awful by the end of the next growing season.

As a rule of thumb, I like to thin a tree a couple of years after reducing it and vice versa, its better than an endless cycle of crown reductions 'back to the old cuts'.

[bareroots]

So thinning is good post reduction intervention then? Any other applications?

 

Could you take off the odd branch of an (excurrent) to reduce sail and hus avoid an unsightly 'topping'? Or is that a silly idea?

[bareroots]

Oh dear, how many more times do we need to re apply the "common sense" that short and fat= GOOD tall and thin= BAD!

 

or is that implicit in this post? or does it not apply to excurrent conifers