Level 1 Tree Inspection Course at Holt Hall Field Studies Centre with David C. Dowson for Forest Schools Level 3.

Intro - 7 a day killed on roads, same as number killed by trees in a whole year.
DD is from TreeLife Limited based in Leicester, and TreeLegal Ltd and a member of the AA Arboricultural Association.

Learning objectives
- Visually identify tree defects from the ground using binoculars and using a mallet and or probe where appropriate.

- Record defects and rate hazards
- determine a course of action, typically one of -
... none
... get advice
... plan to get specific work done - contractor or self if easy (low hanging branches).

Duty of owners and inspectors explained, particularly with regard to "reasonable care".

Claus Mattheck's "Axiom of uniform stress" - no weak point, no breakage.
example antlers.
Growth and competition: trees are 4.5 times stronger than they need to be. Mechanically self-optimised structure which adds material to repair damage. This makes visible bulges, which we can recognise if we know what a "normal" tree looks like.
Sequoia sempervirens is often a good example of normal.

We learnt to do a VTA visual tree assessment systematic diagnosis.

Photos of 12 common defects were discussed -
-Fruiting bodies of Inonotus hispidus on Ash
-Compression fork with embedded bark weakening a limb. A healthy tensile fork often has a ridge.
-Significant bulges can indicate hidden problems, or just healthy healing. Normal may be tapered or cylindrical.
-Ivy can obscure problems and add to the load due to wind and snow.
-Dead bark may indicate dead wood below or infestation.
-Slimes and fluxes are exuded for infections.
-Deadwood can easily be seen when a tree should be in leaf.
-Die back in the crown seen by discoloured or missing leaves, early drop in Autumn or late buds in Spring.
-Cavities may be a weakness if greater than a third the wood gone - will cause bulges nearby.
-Wilting and discoloured leaves.
-Cracks and splits
-Root damage by diggers
www.arborecology.co.uk/arb_vta.htm