Who supplies root deflectors?

[gibbon]

I a looking for a supplier of root deflectors. Anyone know who can supply these, preferably an online order so I can price the job?

[woodplans]

Gibbon,

 

We get ours from these guys:

 

http://www.amenity.co.uk/PDFs/fencing%20and%20barriers%2009.pdf

 

Urban Planting | Green-Tech: Landscaping and Forestry Products

[Bundle 2]

Why do trees root in the top,Mmmm... lets say 1m of soil for arguments sake? ( more like 600mm imo ) Certainly most small roots occur at the surface?

I felt annoyed by the blurb contained in one of the links. Manufacturers endorsement of their own product I suppose. I can see that root barriers have a place in remedial and pre-development design of urban conurbations.....I cant tho see that the "bottomless bucket" is the answer to much. The concept is wrong.

The answer is surely to design the hard landscape structures to accommodate trees ( or dont bother)

In the past, a lack of understanding has given rise to the problems and conflict that get trees a bad name. Its not all the fault of developers tho.

IF rooting was better understood and very POOR choices made about species for location were avoided, a better harmony would result. Urban development with more longevity.

I ve seen developments which go wrong. Numerous trees are destroying the tarmacadum laid down for parking. Its not the pits that are wrong. The space allowed for the trees is inadequate ( when isnt it? ) The tree choice is appalling. Small trees are the preferred option. A misconception from the outset imo.

Then they get pruned ( butchered actually ) at about 7-12 yrs on....really mutilated. Why? Cos grounds maintenence gets their hands on the trees and they probably learnt all they know about trees from the developers who put them in the ground!

They think pruning the feck outta the top will stall the demise of the tarmac. Apart from anything else, the trees will never look like anything other than a sad indictment to...oh, forget it.

But do you know what their answer is? Yeah, you guessed it.

Dig up all the trees, make good the pits and tarmac and then start again with more trees.

UNBELIEVABLE. So this is why I found the self professed genius of " forcing the roots to go where no root has gone before" a bit dull.

I think the trees got more sense than the rest of 'em put together!!

[gibbon]

Wow, thats quire a response. I completely agree, I fact I have just been doing a little research into below groud plating pits and permeable surfacing.

 

In this case the deflectors are for highway tree planting as it seems to be the policy that root deflectors should be installed with new planting. I looked at the job today and it is in fact felling a load of dead highway trees and replacing new standards in tarmac graves. I will probably get to fell these trees in a few years if I'm lucky!

[woodplans]

Bundle,

 

I agree with you, we recently priced a job planting some large ( 40 - 45 cm ) girth trees. The architects spec called for root deflectors in each tree pit plus 300mm of clean drainage fill at 1500mm deep the area available for the tree to root into worked out at 8 m3 !!!

The worst part was that they were not even in a paved area, but 15 metre back from a road in an area of newly seeded grass.

We queried it with the main contractor who's reply was "just do it to the spec" I decided to pass on that job, as i felt the whole exercise was a waste of time.

[Bundle 2]

Mmm...After a bit of digging I found this.......

It would seem to speak for itself although I maintain that it is far from clear the longterm effects on root growth characteristics....I suppose I mean the "habit " adopted by the root mass from the enforced directional influence...and the effect on a mature tree, physologically.....

Somehow I would expect the roots to revert to a "normal" growth pattern once the obstacle has been circumnavigated...meaning the designers must have to be aware of this and the physical benefit of its incorporation into a design scheme, severely limited...

Smiley-Roots & windthrow.pdf

[Bundle 2]

And in the same regard...here is some research that was done with growing mediums with respect root & landscape conflict .

4 me its about doing it right ( or dont bother...) The jury is still out with respect all possibilities but the best choice ( for now ) seems pretty clear...?

Structural Soil.pdf

[gmanntpo]

I agree.. The roots will grow towards the the optimum growth condition area (e.g the top 600 - 900mm) of soil once they get beyond any root guides..

[Giles Hill]

Mmm...After a bit of digging I found this.......

It would seem to speak for itself although I maintain that it is far from clear the longterm effects on root growth characteristics....I suppose I mean the "habit " adopted by the root mass from the enforced directional influence...and the effect on a mature tree, physologically.....

 

I don't think plastic root barriers per se cause any particular problems, so long as there is adequate rooting medium to sustain the tree.

 

Trees growing on hedgerow banks effectively have barriers on both sides - i.e. where the face of the bank meets the air. Similarly differing ground conditions, water courses and foundations can create barriers.

 

In the cases mentioned in your link, of trees being harder to uproot where barriers are installed, I should think this has less to do with the roots runnning deeper, and more to do with the support provided by the barrier itself. Tree roots do make use of underground structures to give themselves additional anchorage and I'd think a root barrier would would provide good anchorage, once the roots had got under it.

 

Regarding root deflectors, my main concern would be that they could eventually girdle the base of the tree, if you used the smaller sized defelctors with larger tree species.

 

PS I liked your brain-eating avatar, where did it come from?

[Giles Hill]

I agree.. The roots will grow towards the the optimum growth condition area (e.g the top 600 - 900mm) of soil once they get beyond any root guides..

 

They may have done their job by then - by protecting nearby kerbs and edgings.