Arboricultural Implication Assessment (AIA)

If a proposed development may have consequences for retained trees, local planning authorities are likely to request an Arboricultural Impact Assessment, or ‘AIA’ report.

The AIA includes evaluation of the direct and indirect effects of the proposed development on retained trees, and recommended mitigation measures to minimise the conflict between the proposed construction area and the trees.

A Tree Protection Plan (TPP) is included.

Arboricultural Method Statement (AMS)

The Arboricultural Method Statement, or ‘AMS’ report, follows on from the BS5837 tree survey and the AIA report. It details how the proposed construction works can be carried out within a tree’s root protection areas or crown spreads of retained trees with minimal impact on the trees.

The AMS is specific to the site; each conflict must be discussed and work methods outlined in detail. The report can include any issue relating to potential conflicts with trees including demolition, temporary ground protection, trenching, new hard surfacing or specialist foundations, ground amelioration for landscaping and site supervision.

Tree Protection Plan (TPP)

The Tree Protection Plan shows the recommended placement of tree protection barriers and the location and type of ground protection required to minimise tree damage. The TPP report may also include details of service runs, working space, ground level changes, site access and storage, landscaping areas and special construction techniques.

This plan is essential for the construction team to design, plan and co-ordinate works so that retained trees are not damaged.