Eucalyptus blamed for Subsidence

[Snowgoose]

Has anyone successfully defended an insurance case against a Euc? Or know a guy that has?

 

Mine is 14m from my house and the initial test pits have found only miniscule root hairs near the cracking, but my insurers are trying to pin it on suspect No 1. I've read a few of the past posts but most just say take the tree down.

 

Somebody mentioned guidelines in The Body Language of Trees? Will these help my cause.

 

The tree is about 25 years old and solid. I cannot bear to take it down. The soil is a clay type.

 

I need the Clint Eastwood of defending poor Eucs!

 

Many thanks in advance

 

S

[Steve Bullman]

you mention miniscule root hairs near the cracking. its a common misconception that the roots themselves are physically causing the damage to buildings. its actually the soil heave causing the subsidence......unfortunately you have a very vigorous water loving tree growing in clay soil, the worst soil type for subsidence.....in these circumstances id probably say the insurance companies report is more than reasonable

[djbobbins]

We had a euc at the front of our house (6-7m away and about 10m+ tall) and minor subsidence to both our own house and the neighbours.

 

I was not clear on cause and effect but felled it anyway - the upside is that the lawn and other plants are greatly improved, and once the wood had seasoned I had a decent stock of firewood for a while. So it's not all bad news!

 

P.S. Apologies that this is about as helpful to your argument as a chocolate teapot!

[educated arborist]

its the OCA subsidance journal u'll need 2006 i think, a local consultant should do you a verbal apprasial for about £75-£100.

[sean freeman]

Go here Downloads | Risk Limitation Strategy for Tree Root Claims and download the Risk limitation strategy read through chapter 6 'Levels of Evidence' and then consider whether you think your tree would fall into any of those criteria, then you will be better placed and prepared to mount a defence (or not) of your tree and the claims of its relationship to the subsidence.

 

It is far from straight forward nor is it simplistically causal...that you have clay soils is not good since as Steve B indicated these can be highly reactive to alterations in relative moisture content.

 

It is very very hard to definatively prove (probably impossible) that any specific piece of vegetation is not having an influence on soil moisture, and that fluctuations in soil moisture are not having an impact on the physical structure of the soil body..hence any structure built on or in that soil body.

 

That having been said do read the LTOA document.

 

One final aside I personally have never read any convincing evidence that Eucs are any more demanding in their rates of evapotranspiration than other tree species..the modelling and maths required to put figures on those rates are quite literally frightening.

[Bundle 2]

Hi Sean,

Do you use this criteria for claims of this nature in Australia, either directly or as a point of reference?

I imagine that certain of the issues are the same but that foundation construction is not really replicated between the two locations...?

Tim.

[sean freeman]

I try very hard to drag clients and insurers kicking and screaming into science when it comes to these kinds of claims made about trees...and yes sometimes that means the tree is found to be a significant factor, sometimes not.

 

Sadly we have an appauling Australian Standard (AS2870) when it comes to considering the potential impact of vegetation on building foundations...it could have (may have!) been written by an underachieving inattentive high school student biology student.

[b101uk]

Just remember there can be vast differences between “clays” which is a general term

 

Clay can range from something that is quite pervious and expand & contracts dependent an moisture levels to a hard shale which is almost impervious to water/moisture.

[Rupe]

If its only 25 years old then it has plenty of time left to get much bigger and more destructive. All cases are different, but you have one of the hardest species of trees to defend in these cases.

 

If it were Leylandii, we would all say fell it. Not because its definatly the cause but because it could be and its "only" a Leylandii. Well Eucs are easily as destrcutive as Leylandii, if not more so, yet people seem to like them more and get emotional about them but fellign them just in case is still a reasonable plan. In my mind its "only" a Euc, and its "only" 25. Fell it now and put something nice in.

 

Chances are (again all cases are different) your house would be cracking with no trees there at all! Poor building quality is the most common cause of subsidence, and trees only help start the process off. if the insurance is not valid unless you fell the tree then fell it, and they will have to pay if the subsidence gets worse.

[Snowgoose]

Many thanks for the replies one and all. I shall see if I can save it but its looking like they will get their way, or cease to insure me.