Channel 4 now

[Tony Croft aka hamadryad]

Not neccessarily bone dry Tony, if the house is on clay soil it will be damp or saturated soil under the house too

 

yes i guess, still dont explain such depth for roots, i guess a sandy clay might have much better macro pore structure and hence allow deeper aeration?

[Mark Bolam]

Wasn't very tree-friendly, was it?

 

If you have a tree within 15m of your house, you may have problems.

 

There aren't many round here that haven't!

 

At least it did mention that there were a number of different factors and situations.

 

Pollarded a medium sized Willow a few years back at the insistence of an insurance co. that was 55m from the house.

[William]

yes i guess, still dont explain such depth for roots, i guess a sandy clay might have much better macro pore structure and hence allow deeper aeration?

 

The Forestry Commission has produced research on root depth http://www.forestry.gov.uk/pdf/FCIN078.pdf/$FILE/FCIN078.pdf. Its not directly related to subsidence I know but if conditions are suitable for roots beneath foundations at the edge of a building they could easily be there. This on its own would not result in subsidence though.

[janey]

Wasn't very tree-friendly, was it?

 

If you have a tree within 15m of your house, you may have problems.

 

There aren't many round here that haven't!

 

At least it did mention that there were a number of different factors and situations.

 

Pollarded a medium sized Willow a few years back at the insistence of an insurance co. that was 55m from the house.

 

I saw an interview and preview of the program on the BBC morining news the morning before the show was aired. I think I made the right choice not to actually watch it, from the clips that I saw. It was so predictably sensationalist and lacking in facts - good for TV ratings but bad information for the general public and very short of a balanced approach.

[arb culture]

boat house maybe?

 

Like it

 

The day I get called to do a subsidence report on a house boat is the day I know trees are getting blamed for too much. This house was a normal semi-detached built in the 1950's or 60's on an unexceptional clay loam.

 

Mind you, thinking of weird subsidence clams, I once saw a tree related subsidence report attributing damage to a cherry tree growing within 5m of a house. Thing is though, the cherry was in a large plant pot with no roots in the ground at all:confused1:

[arb culture]

yes i guess, still dont explain such depth for roots, i guess a sandy clay might have much better macro pore structure and hence allow deeper aeration?

 

Roots often go a lot deeper and into places which are more inhospitable than you seem to think Hama.

 

My previous post should read 1cm diameter though, not 10cm - typo, sorry.

[Tony Croft aka hamadryad]

Roots often go a lot deeper and into places which are more inhospitable than you seem to think Hama.

 

My previous post should read 1cm diameter though, not 10cm - typo, sorry.

 

Roots may well indeed go into places that suprise, but they DO NOT go where there is no oxygen, and definatley not where it is anaerobic.

 

trees may and do throw roots into the river, but they are balanced with roots in ground not waterlogged and there is oxygen in the water.

 

grown in land mass with a high water table, they cant survive below the water line, and fail due to a shallow rooting depth, proving that they cant function in such inhospitable circumstances.

 

so, what im saying is, what pecial circumstances allowed YOUR roots to be at 2m? snady clay i would get, sand I would get.

 

maybe temporary dessication cracks (pore spaces allowing root development) in a heavy clay, or excsessive worm activity (under a house)

[arb culture]

Roots may well indeed go into places that suprise, but they DO NOT go where there is no oxygen, and definatley not where it is anaerobic.

 

trees may and do throw roots into the river, but they are balanced with roots in ground not waterlogged and there is oxygen in the water.

 

grown in land mass with a high water table, they cant survive below the water line, and fail due to a shallow rooting depth, proving that they cant function in such inhospitable circumstances.

 

so, what im saying is, what pecial circumstances allowed YOUR roots to be at 2m? snady clay i would get, sand I would get.

 

maybe temporary dessication cracks (pore spaces allowing root development) in a heavy clay, or excsessive worm activity (under a house)

 

No special circumstances - 2m depth is not unusual.

[arb culture]

Roots may well indeed go into places that suprise, but they DO NOT go where there is no oxygen, and definatley not where it is anaerobic.

 

I'm sorry but you are wrong.

 

Try googling 'tree root anoxia' (and similar) for quite a lot of scientific papers on the subject dating back several decades.