Dr Martin Dobson

Levels of evidence and Levels of evidence and required action required action

Part 1Part 1

London Tree Officer’s AssociationLondon Tree Officer’s Association

Now runs to 97 pages!

And includes all trees, not just those owned by

local authority

Main aims of LTOA guidanceMain aims of LTOA guidance

Manage risk

Avoid spurious claims

Deal with valid claims quickly and effectively

1. Manage the risk

How do you know what’s high risk?How do you know what’s high risk?

2. Avoid spurious claims2. Avoid spurious claims

1. Site geology

2. Crack pattern description and interpretation

3. Crack and/or level monitoring

4. Time of development of damage

5. Tree/shrub information – position of tree in relation to damage

6. Root identification

7. Trial pits (foundation depth)

8. Soil desiccation

9. Drain survey

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Dec-99 Mar-00 Jun-00 Oct-00 Jan-01 Apr-01 Jul-01

Cra

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Crack 1V

Crack 2V

Crack 3H

Crack 4

Crack 5H

Crack 6V

Crack 7D

Crack 8V

Crack 9H

Crack 10H

Heave!

It must be the trees!

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Crack 1

Crack 2

Crack 3

Crack 4

Crack 5

But it’s not!

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Sep-97 Jan-98 Apr-98 Jul-98 Nov-98 Feb-99 May-99 Aug-99 Dec-99

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Crack 1

Crack 2

Crack 3

Crack 4

Crack 5

Crack 6

Crack 7

Crack 8

Crack 9

Crack 10

It is the tree this time!

2. Avoid spurious claims2. Avoid spurious claims

1. Site geology

2. Crack pattern description and interpretation

3. Crack and/or level monitoring

4. Time of development of damage

5. Tree/shrub information – position of tree in relation to damage

6. Root identification

7. Trial pits (foundation depth)

8. Soil desiccation

9. Drain survey

3. Deal with claims quickly and 3. Deal with claims quickly and effectivelyeffectively

1.Visit the site

2.Assess the evidence

3.Communicate with the claimant

4.Carry out precautionary pruning or fell in good time

Trees covered by a TPOTrees covered by a TPO

Trees covered by a TPOTrees covered by a TPO

Trees covered by a TPOTrees covered by a TPO

Tree Preservation Order applications can be refused if evidence is inadequate or incomplete

However, there is liability to pay compensation if a loss is suffered as a consequence of a refusal

But, the application for compensation must be made within 12 months of the refusal or within 12 months of a dismissed appeal

Trees covered by a TPOTrees covered by a TPO

If a tree is causing an ‘actionable nuisance’ then the TPO does not apply.

But the onus is on the person felling the tree to prove the nuisance.

Often the evidence is with the claimant rather than the tree owner, thus, it is best to encourage the claimant to submit the application.