Local planning authorities can produce Supplementary Planning Guidance (SPG) on any topic where they think more information is needed. This can include issues such as Biodiversity, Street Trees, or Landscaping but also the development of a particular area, such as an area masterplan. They may also adopt non-planning documents, such as a Biodiversity Action Plan or Nature Recovery Action Plan, as Supplementary Planning Guidance. It is up to the planning authority to decide which issues need Supplementary Planning Guidance.
When new Supplementary Planning Guidance is written, there is usually a six-week (or more) consultation period in which you can comment, but unlike the Local Development Plan, there is no examination. Supplementary Planning Guidance must comply with National planning policy and the Local Development Plan.