Planning conditions in arboriculture

Trees are living organisms that often get tied-up in with new planning and development projects. The design of the proposed development and how it relates to the trees on and adjacent to the application site aside, if the Local Planning Authority (LPA) considers the proposed development acceptable in policy terms then they will grant consent (or recommend consent, in cases where the application goes to committee). Consent comes in the form of a decision notice, which sets out the limitations of the proposed development and what further elements must be satisfied before the development is completed and handed-over to the applicant. Depending on the type of planning application, the decision notice may grant consent in full (including householder applications) or in outline. Decision notices for full (and householder) applications come with planning conditions attached, which have to be discharged at the relevant stages of the development process (e.g. pre-commencement, pre-brick and beam, pre-occupation) or otherwise control the proposed development in accordance with already-submitted documents (i.e. performance conditions), and outline applications come with reserved matters that for all intents and purposes draw-out the planning process and reduce up-front expense costs to the applicant. When applications for reserved matters are submitted, the LPA can on the back of this consent the application subject to relevant and appropriate planning conditions. For example (and explained more below), an LPA may request as a reserved matter an Arboricultural Impact Assessment (AIA), which following approval as a reserved matter the LPA can then condition an Arboricultural Method Statement (AMS).

At this point, it is necessary to understand what the difference is between an AIA and an AMS. An AIA is a report that makes a judgement with regard to the impacts to the trees from the proposed development and the means of mitigating these impacts, and typically is provided at the planning stage prior to a decision notice being issued to the applicant; this is because an AIA gives context to and in hopefully many cases justifies the proposed development (subject to appropriate design and adherence to policy), and therefore hopefully informs the arboricultural consultee at the LPA and the case officer that the proposed development should be considered for consent in the context of trees exclusively (i.e. provided once RIBA Stage 3 has been completed, which is often when a full planning application is submitted to the LPA). An AIA will usually provide a draft tree protection plan (TPP), and also an ‘outline’ (‘heads of terms’) AMS that likely works on an element of assumption that may sometimes be sufficient – the TPP at least will detail the means of mitigation discussed within the AIA.

RIBA Plan of Work
The RIBA Plan of Work 2013 (source).

An AMS, on the other hand, is a document that provides a clear and detailed methodology for RIBA Stage 5, which is the construction phase of the project, and uses the technical designs of RIBA Stage 4 to specify appropriate construction methodology to protect the retained trees within the application site and those ones adjacent that will be affected by the development. In this context, an AMS will include the relevant details including construction traffic management, material storage, foundation design, service installation, and landscaping, and specify the manner in which these operations will be undertaken and the tree protected so that they don’t die or have a shortened life expectancy due to damage during the construction phase, including by providing a detailed TPP and specifying a clerk of works schedule. A detailed AMS can only be provided as a planning condition, because before this stage the AMS will have to speculate on certain matters, which is generally not acceptable and doesn’t work effectively when tendering a development out for construction. More detail on both types of report can be found by reading BS 5837:2012.

In order to appropriately protect trees during the development process, which is required by law, the LPA must pay careful attention to the use of planning conditions and reserved matters. These must always be relevant in context, as must they always be worded appropriately. A failure to word conditions and reserved matters in this manner means that they are not fit for purpose. In order to understand how the LPA will best use conditions to control development and protect trees, let us entertain a few examples that relate to full planning applications.

Cellweb access and trees
Ground protection installed adjacent to trees to allow for vehicular access through a wooded area, which will be specified in full detail as part of a detailed AMS but covered at least by way of suggestion in an AIA to manage tree impacts.

Scenario 1: AIA provided at full planning; AMS required as pre-commencement (very frequent)

Imagine that you have a large plot of land that currently has three residential dwellinghouses with a shared communal garden, and you want to demolish all three dwellinghouses and construct a duo of larger dwellinghouses on separate plots. There are many trees throughout the site, including adjacent to the existing dwellinghouses, and you want to retain most of the trees to incorporate into the two new plots (removing only the small ornamental trees and those that are in clear structural and/or physiological decline). You submit an AIA with the planning application, which demonstrates that the proposed development can be achieved, and is acceptable in policy and arboricultural terms. A draft TPP is provided alongside an outline AMS that shows that the retained trees can be protected during demolition and construction work, though you have yet to develop technical designs. The LPA logically recognises this and attaches a pre-commencement detailed AMS, which must be discharged before any work can begin on site, to ensure that the retained trees are sufficiently protected.

Scenario 2: AIA provided at full planning with outline AMS; performance condition attached (frequent)

Imagine that you have a vacant plot of land that has two large oak trees at the top right corner. You want to build a house at the bottom left corner, far away from both oak trees. The LPA has rightly requested an AIA to support the full planning application, because they must appropriately consider trees in the context of planning and development. The AIA demonstrates that the proposed development will in no way impact upon the two oak trees, and is therefore acceptable in policy and arboricultural terms. The AIA provides an outline AMS including a TPP that allows easily enough room for construction activities whilst sufficiently protecting both oak trees. The LPA logically recognises this and attaches a performance condition to the decision notice requiring full adherence to the AIA including the TPP.

Scenario 3: AIA provided at full planning with a detailed AMS; performance condition attached and pre-occupation condition attached (very infrequent)

Imagine you have a large plot of land that currently has a private boarding school throughout its grounds, and you want to demolish all of the school buildings and construct a new school in its place, because the existing buildings are all in poor condition. There are trees throughout the site though generally away from the existing buildings, and those adjacent to the buildings are to be removed to facilitate the development. You do not want to deal with the myriad details arising from pre-commencement conditions for such a large project that may take many months to fully discharge, and want to simply start building as soon as you get the decision notice through granting consent. You are very confident that you will obtain planning consent, because the LPA has supported the proposed development throughout the planning process including at pre-application, and there is significant community support for the proposed development following completed public consultations. Therefore, you have completed many of the technical details of RIBA Stage 4 already, and provide these details at full planning with an AIA and a detailed AMS demonstrating that the proposed development is both acceptable in policy and arboricultural terms, and can be completed and the retained trees appropriately protected. The LPA logically recognises this and attaches a performance condition to the decision notice requiring full adherence to the detailed AMS, and also attaches a pre-occupation planning condition requiring that the clerk of works detailed within the AMS be submitted as proof that the AMS was adhered to throughout and that the trees were sufficiently protected (e.g. through submitting a series of reports that accompanied each clerk of works visit).

Now let’s take a look at some scenarios that should not occur at full planning, else run the risk of trees being inappropriately considered and conditions being insufficient to protect the trees, for clear and evident reasons:

Scenario 4: No AIA at planning; AIA required as pre-commencement

You are the landowner for Scenario 1 (above). You do not submit an AIA to the LPA at full planning, because you want to see if you can obtain planning consent without this expense. The LPA reviews the proposed development details, and grants consent with a pre-commencement condition requiring that an AIA be provided. There is no mention anywhere of an AMS as a pre-commencement condition.

Scenario 5: Detailed AMS requested by LPA at planning; intent to attach performance condition

You are the landowner for Scenario 1. You submit an AIA to the LPA at full planning. The LPA however request a detailed AMS or they will refuse the application. You have only developed detail to RIBA Stage 3, and have yet to design to technical detail the project, because you don’t want to spend that money before obtaining planning consent. You ask your arboricultural consultant to provide a detailed AMS, which they try to do but cannot fully complete. The LPA accepts this and attaches a performance condition to the decision notice that requires full adherence to the details of the ‘detailed’ AMS.

Scenario 6: No AIA at planning; no arboricultural conditions attached

You are the landowner for Scenario 1. You do not submit an AIA to the LPA at full planning, because you want to see if you can obtain planning consent without this expense. The LPA reviews the proposed development details, and grants consent without any arboricultural conditions attached. You can therefore begin works at the site once all other pre-commencement conditions have been discharged, and without any tree protection measures.

Now, let us understand what appropriately-worded planning conditions might look like. Based on the above scenarios, we have three appropriate types of appropriate planning condition:

  • pre-commencement AMS: No works will take place at the application site, until a detailed AMS has been submitted to the LPA and approved in writing. The AMS will include all relevant details to protect the retained trees, including a detailed TPP. Relevant details may include but are not limited to construction methods, construction traffic management, demolition methods, finished levels, ground protection, landscaping methods and materials, material storage, service runs, and tree protection barrier fencing. The AMS will also include details of a clerk of works schedule that specifies arboricultural supervision at appropriate stages of the development process. Any variations to the details of the AMS must only be undertaken after the proposed variations have been agreed in writing by the LPA.
  • performance condition: The proposed development shall be completed in full adherence to the arboricultural details submitted to the LPA (documents and plans specified here). Any variations to the details of the documents and plans must only be undertaken after the proposed variations have been agreed in writing by the LPA.
  • pre-occupation condition: Prior to the occupation of the site, the LPA will be provided with clear and obvious proof that the details of the AMS have been adhered to, including the clerk of works supervision schedule. Proof will be demonstrated through the submission of a series of brief reports or single larger report, which summarise the details of each clerk of works visit, including where relevant photographic evidence of adherence to the AMS and TPP.

With regard to outline applications, the process as detailed above broadly applies, though with the following deviations. Specifically, the LPA may require an AIA as a reserved matter, and subsequent to the approval of this condition a detailed AMS. However, where an outline application will impact upon trees, which may include tree removal or site new built structures adjacent to trees to be retained, the LPA is (in accordance with planning law) permitted to request an AIA to support the outline application to demonstrate that it is acceptable in policy and arboricultural terms. In such an eventuality, it will instead be necessary for the decision notice for the outline application to include a reserved matter requiring a detailed AMS be approved prior to any works starting on site.

Trees and construction
Details of tree protection measures will be specified within a detailed AMS.

In situations where a large site is to be completed as a phased development, the LPA must co-ordinate with the applicant, in order to ascertain the most effective use and wording of planning conditions and reserved matters, because there is a real risk of the phased nature of the development staggering the development of technical designs that will impact upon trees. This matter is too complex and varied to cover here, though the above principles should be applied, to achieve the desirable end as regards trees and the protection of.

From the above, it should be clear how planning conditions relate to arboricultural matters, in the planning process. However, if you have any queries, please leave a comment below.



Planning conditions in arboriculture