A tree plan is a visual depiction, with required notations, of existing trees and site conditions, proposed site changes, how tree density requirements will be met, and how conserved trees will be protected. Tree plans are required in ordinances that regulate trees during land development.
There are many factors and conditions on a development site that go into which existing trees, in which locations, can and should be successfully protected and conserved, and where new trees can and should be planted to thrive and function best to meet tree ordinance intent and community goals. The tree plan brings all these factors together in a graphic depiction of how tree density and other tree ordinance requirements will be met.
The tree plan–usually called a tree conservation plan, tree preservation plan, or tree canopy plan–becomes the primary, official document showing how a property owner or their agent proposes to meet tree ordinance requirements. Once approved, it may only be modified with further approval by the tree ordinance administrator, community arborist or other designated official.
In addition to the tree plan, a tree protection plan or tree planting or replacement plan may be required, either a separate plan or included on the tree plan. Tree protection plans show how, and where, conserved trees will be protected, and tree planting plans and tree replacement plans show where, and which, new trees will be planted on the site to meet minimum tree density requirements.
As part of the development of the tree plan, a tree survey is usually required so that the location, species and size of all existing trees, groups of trees, and tree stands found on the site can be depicted on the tree plan. Some communities require that location information include the location of the trunk and the location of the critical root zone for each tree or tree group.
Tree plans are submitted to the appropriate department and reviewed by the city arborist or other designated staff for approval. It is a standard requirement that tree plans must be approved before a land disturbance permit or other development permit can be issued for an applicable site.
A tree plan, tree protection plan, or tree planting plan may be required as part of an application for other required permits outside of the land development process. An approved tree protection plan may be required before a right-of-way encroachment permit can be issued. An approved tree planting plan may be required before a tree removal permit can be issued, for replacement tree planting after trees are removed.
PRE-PLANNING SITE VISIT
A visit to the subject site prior to the development of a site by the property owner or their agent along with the designated staff or arborist may or may not be required, but is often done to initiate the discussion on which trees should be conserved, and where tree density should be distributed. The discussion should also include a review of how conserved trees are to be protected and other technical standards requirements that will be important for the development of the plan. It is also important to discuss during the site visit where buildings, driveways, materials storage, temporary buildings, ingress and egress drives, equipment washouts, and vehicle travel and parking areas should be located.
TYPICAL PLAN REQUIREMENTS
Think about the information you need to made sound decisions on whether or not to approve a plan to conserve and plant trees to meet minimum tree density requirements. You will want to have a complete picture of all activities, structures, and processes occurring on a site that will impact the tree density, health, and benefits.
To help with making sound decisions and developing a successful plan, communities typically require that the tree plan be developed and certified by an ISA certified arborist or registered forester to ensure that someone with sound technical expertise was involved in determining how the tree ordinance requirements will be met.
Requirements for tree plans typically include specifications for what information must be included. They may also require that a tree survey be completed to record the location, species and size of all existing trees on the tree plan. Then trees proposed for conservation and planting locations of new trees are depicted. The existing grade and proposed changes to the existing grade must be depicted. Existing and proposed locations of permanent and temporary structures, utilities, impervious surfaces, and infrastructure are typically required.
Typical of many tree ordinances requiring a tree plan, Gwinnett County, in Section 320-90. – Tree preservation and/or replacement plan, requires the following information on their tree plan:
- Project name, land district, land lot, parcel, north arrow and scale.
- Developer’s name, address, and telephone number.
- The name, address, and telephone number of the authorized registered professional, registered forester, or certified arborist, in accordance with the requirements of Section 320-90.1, above, and the Seal or statement of professional qualifications of said person (which may be attached separately).
- Delineation of overhead power lines and transmission lines.
- Delineation of all minimum yard areas, buffers, and landscape areas as required by this UDO or conditions of zoning, special use or variance approval.
- Total acreage of the site and total acreage exclusive of all zoning buffer areas.
- Delineation of all areas located within a 100-year flood plain.
- Existing trees to be retained in Tree Protection Areas:
- Trunk location and size (to the nearest inch in diameter at 4.5 feet above the ground), of individual trees proposed to remain for credit toward meeting the minimum Tree Density Standard on the property.
- Groups of three or more trees whose driplines combine into a single Tree Protection Area may be outlined as a group and their number, by diameter, shown in the Summary Table.
- If the number and size of all existing trees to remain on the site exceeds the required tree density standard for the entire site, only those trees required to meet the minimum Tree Density Standard must be shown.
- All Tree Protection Areas are to be outlined and labeled.
- Tree Protection Measures:
- A detail or description of the protective tree fencing to be installed, and the location of such measures, which at a minimum shall follow the dripline of all trees to be retained along adjoining areas of clearing, grading, or other construction activity.
- Measures to be taken to avoid soil sedimentation intrusion into Tree Protection Areas, and the location of such devices.
- Proposed location of temporary construction activities such as equipment or worker parking, materials storage, burn holes, equipment washdown areas, and entrance pads.
- Proposed type and location of any tree save area signs or other pertinent signage.
- If replacement trees are proposed to be planted in order for the property to achieve the required Tree Density Standard, the replacement trees shall be shown and their spacing and caliper identified, to the extent needed to achieve the minimum requirements. Trees grouped together in tree planting areas may be listed on the Summary Table by total number in the grouping, by size.
- A Summary Table of the number of existing trees to remain by diameter to the nearest inch at 4.5 feet above the ground for preserved trees and for new trees to be planted by caliper at 6 inches above the ground for replaced trees, shall be shown along with calculations showing the tree density achieved for the site. Additional credits shall be noted where applicable.
- Tree Canopy Calculations.
- The plan sheet which shows the grading plan, including existing and proposed contour lines, shall indicate the dripline location of all Tree Protection Areas through the use of shading on the plans. The exact location of each tree is not desired to be shown, only the limits of the Tree Protection Area and any other areas which are not to be disturbed.
Douglas County in Section 820. – Trees to be provided and retained. in Division IV. – Tree Conservation, within Article 8. – Landscaping, Buffers and Tree Conservation of the county’s Unified Land Development Code, includes the following requirements for information that must be depicted or noted on the tree preservation plan:
- Definition of spatial limits:
- Limits of land disturbance, clearing, grading and trenching
- Tree save areas
- Specimen trees
- Areas of re-vegetation
- Detailed drawings of tree protection measures and their location:
- Location, species, size (DBH) of existing significant trees and an indication of which trees will remain on site
- Tree protection fences
- Erosion control fences
- Tree protection signs
- Tree wells
- Aeration systems
- Transplanting specifications
- Staking specifications
- All utility lines existing and proposed, including irrigation and electric lighting lines. The applicant shall coordinate the location of these utility lines with the utility companies in order to prevent root damage within the critical root zones of protected trees, and to minimize damage to trees located in protected zones.
- Procedures and schedules for the implementation, installation and maintenance of tree protection measures.
- Other applicable drawings as determined by the County Arborist.
They also require a tree survey that includes the size, species and location of all existing trees 18 inches DBH and larger, specimen trees, and trees 4 inches DBH and larger that the applicant proposes to conserve for tree density credit.
PLANS REVIEW PROCEDURES
The plans review procedures should follow the standard procedures for reviewing site plans that accompany the land disturbance permit application or other permit application for which a tree plan is required.
The plans reviewer should be given an appropriate amount of time (15 to 30 days) to review the plans, make a site visit to evaluate the plan, and make any comments and recommendations for changes to the applicant.
A site visit is critical to validate the plan before the plan is approved. Even if a pre-planning site visit was made, the plans reviewer should verify on-site that the plans are practical, reasonable and accurate, and will meet both the requirements and the intent of the tree ordinance.
Once a tree plan is approved, site inspections to monitor compliance with the tree ordinance and tree plan are important.
Typically, communities require a site inspection after the installation of tree protection fencing, but prior to the commencement of any land disturbance activity.
Periodic site visits are often made, although not necessarily required by the tree ordinance, to monitor ongoing compliance with the tree ordinance and tree plan.
A final inspection is almost always required by the tree ordinance prior to the issuance of a certificate of occupancy for a site, to make sure that all requirements of the tree ordinance and tree plan have been met.
Oftentimes unforeseen circumstances require that a plan be modified to best meet the intent of the tree ordinance and constraints of the developer or owner. For example, certain tree species may not be available, and a suitable species can be substituted. Rock may be found near the soil surface in certain locations where trees were to be planted and another location on the site may have soils better suited for planting trees.
Once these and similar changes are approved by the arborist or administrator, plans should be modified and resubmitted, or notations made on the original plans by staff, to make sure that an accurate, official record is made of the site as built. These final plans and notations should be required prior to the issuance of a certificate of occupancy for the site.