Walnut cause heave?

[James Atkinson]

Today I was asked to quote on a removal of a walnut tree around 5 metres away from a old stable block. Now I know these older buildings tend not to have great foundations. Would you recommend a removal over stages on a tree like this? I would usually just go ahead and take it out but felt this would just be worth checking. Any help would be much appreciated.

 

[Mick Dempsey]

Soil type?

[Gary Prentice]

Staged removals are considered as pretty pointless. If things are going to move, they're going to move.

[James Atkinson]

Soil type?

Very light. It would have been marsh land until relatively recently in history so organic matter. But obviously I have not done a soil test to back this up, but I’m fairly confident.

[Mick Dempsey]

A few years (18) ago I had a very big oak near a house to take out in Woking, I was nervous of heave and consulted a consultant mate, he checked on the geology map, saw it was sandy and told me to crack on.

 

 

[benedmonds]

35 minutes ago, Gary Prentice said:

Staged removals are considered as pretty pointless. If things are going to move, they're going to move.

Ditto

[Gary Prentice]

1 hour ago, Mick Dempsey said:

A few years (18) ago I had a very big oak near a house to take out in Woking, I was nervous of heave and consulted a consultant mate, he checked on the geology map, saw it was sandy and told me to crack on.

 

 

We were told at college that the lecturer had questioned the accuracy of geological maps at a BGS/subsidence seminar, only to be informed that they may accurate to +/- 20 miles. 

 

Looking at something this evening and one side of the street is one soil type, the other another. Luckily both are low shrink/swell soil types so it's immaterial but if they were vastly different I wouldn't want to be making decisions based on a map.

[Mick Dempsey]

Wjh

4 minutes ago, Gary Prentice said:

We were told at college that the lecturer had questioned the accuracy of geological maps at a BGS/subsidence seminar, only to be informed that they may accurate to +/- 20 miles. 

 

Looking at something this evening and one side of the street is one soil type, the other another. Luckily both are low shrink/swell soil types so it's immaterial but if they were vastly different I wouldn't want to be making decisions based on a map.

What’s your take on heave Gary? Ever seen it?

[Stubby]

36 minutes ago, Mick Dempsey said:

Wjh

What’s your take on heave Gary? Ever seen it?

After 10 pints and kebab I saw it once ......./...

[Gary Prentice]

38 minutes ago, Mick Dempsey said:

Wjh

What’s your take on heave Gary? Ever seen it?

Never seen it as most of my tree working life has been up north. 

 

Giles Biddle showed some photos of a property where heave was still occurring twenty/thirty years after the tree had been removed!

 

Subsidence and heave are incredibly complex. Giles showed some level monitoring of a row of terraced houses with a row of pretty much identical planes to the front. Some houses were moving, some were not and he admitted no one could explain why.

 

Like most tree related stuff, assumptions are made to the best of anyone’s ability based on observation, experience, local knowledge and available current best practice. And we’ll still be wrong every now and again.