Support the water, nutrient, atmospheric gas, and climate regulation ecosystem service benefits provided by vegetation on site by maintaining or establishing regionally appropriate vegetative biomass.
- Conserve and/or restore vegetation biomass on site to a level appropriate to the site’s region.
- Determine the terrestrial biome for the site by using the World Wildlife Fund Wildfinder, www.worldwildlife.org/science/wildfinder.
- Determine the existing site biomass density index (BDI) and planned site BDI.
- Determine the points earned in accordance with the site’s terrestrial biome and the difference in site BDI according to Tables 4.8 B-E in the Documentation guidance section of the SITES v2 Reference Guide.
Calculate existing BDI for the site as it stands prior to site design (see Pre-Design P2.2: Conduct a pre-design site assessment). Planned BDI is calculated for the site as designed and anticipated within 10 years of vegetation installation.
- On greenfield sites, carefully design the site to minimize disruption to existing appropriate vegetation.
- On brownfield sites, carefully design the site to achieve planned BDI 10 years following landscape installation. The long-term capacity of a site to deliver ecosystem services is compromised by overplanting a brownfield site to achieve a target BDI level prematurely.
- Green walls can increase BDI without changing the overall development footprint.
- Be careful to select shade-tolerant and sun-tolerant species that will adjust in the understory as trees and shrubs mature.
- Use trees, green roofs, or vegetated structures (e.g., trellises) to cover non-vegetated surfaces such as walkways, roofs, or parking lots. Select vegetation-based methods to achieve stormwater management goals for the site.
- Before the design phase, examine the appropriate table for your biome (Tables B through E) to make sure that you do not unnecessarily add more layered vegetation than you can earn credit for. Many of the biome tables are limited at the upper end, e.g. Table 4.8C ranging from <1 to >3 is the same point value as going from <1 to >5 planned BDI.