At junctions, the sight-splay can be divided into two visibility zones. The type of planting considered suitable within sight-splays is set out in the following table: 

Planting	Zone A	Zone B
Existing trees	Typically, no trees permitted. However, in exceptional cases trees may be retained. Final decision to be made on-site in consultation with the local Highway Authority and Planning Authority	Trees may be retained. Final decision to be made on-site in consultation with the local Highway Authority and Planning Authority
New trees	No trees permitted	Trees may be permitted. The precise location should be agreed with the Highway Authority
Groundcover	Groundcover permitted providing the plants do not generally exceed 600mm in height when mature	As for Zone A

All new trees should be of slender girth when mature and have trunks clear of side-growth to a height of 2.1m, or 2.4m if adjacent to a cycle route. 

Grass is not precluded from the areas of sight-splays, but these areas tend to be small and awkwardly shaped, and consequently expensive to maintain. Trees may be allowed, but the locations shall be agreed on-site with the Highway Authority.