C4.5: Conserve Special Status Vegetation – Above Green

(4 points)

INTENT

Protect existing ecosystem services by identifying and conserving all vegetation on site designated as special status by local, state, or federal entities.

REQUIREMENTS

This requirement applies only to plants designated as special status by local, state, or federal entities. These plants may include, but are not limited to, heritage or legacy trees, specimen trees (as designated by a local tree board), rare and endangered species, rare vegetation in a unique habitat, and unusual genetic variants of a particular species. Native plant communities and cultural landscapes are addressed in other credits.

Establish Vegetation and Soil Protection Zones (VSPZs) to protect special status trees and other plants (see Pre-Design P2.3: Designate and communicate VSPZs).
Ensure the section of the site assessment (See Pre-Design P2.2: Conduct a pre-design site assessment) is complete and documents locations of trees or other plants with special status designations.
Ensure the section of the site maintenance plan (See O+M P8.1: Plan for sustainable site maintenance) is complete and describes the ongoing management activities to protect the integrity of the VSPZs, including a description of how the critical aspects of the special status plants’ culture and habitat are being protected and maintained (e.g., hydrology, associated plant communities, exposure).

Note: VSPZs can encompass one plant or can include several plants in a group (see Pre-Design P2.3: Designate and communicate VSPZs).

RECOMMENDED STRATEGIES

Design the site to minimize harm to special status trees and other plants.
Consult with local experts qualified in plant health and safety to determine appropriate special protection measures.
Additional planting within the one foot (0.31 meter) radius per inch (2.54 centimeter) DBH should be avoided. Planting here runs a high risk of damaging tree roots and soil chemistry and having other negative impacts due to excessive irrigation.
- Planting should be limited to 25 percent of the area under the tree canopy or the area within one foot (0.31 meter) radius per inch (2.54 centimeter) DBH and must be done in consultation with a certified arborist or other appropriately qualified professional.
Protect the root zone of trees found on site.
- Try to protect groups of trees rather than individual trees.
- Design utility access away from the soil and roots of trees.
- Reduce the need for utility trench work through strategic placement of utilities.
- Where utility trench work is necessary, use air excavation to expose tree roots without damaging them (according to ANSI A300 Part 5).
- If applicable, consider using directional boring technology (e.g., “mole,” “Ditch-Witch”)
- For trees, ground-penetrating radar (GPR) or air excavation can be used to determine the location of tree roots.