The USGBC’s LEED is a program of land and building development practices whose goal is to achieve sustainable green building www.usgbc.org. The LEED Reference Guide LEED for New Construction v2.2 organizes the practices into five categories, including Sustainable Sites, Water Efficiency, Energy and Atmosphere, Materials and Resources, and Indoor Environmental Quality. Required practices (“Prerequisites”) and optional practices (“Credits”) are listed in each category. Green building projects are certified by the USGBC according to how many Credits are achieved (on top of the Prerequisites).
Many of the practices have implications for landscape, site, and garden construction and maintenance. Some implications are obvious for example requiring use of efficient irrigation systems and native plants. Some implications are less obvious, going far beyond the immediate requirements of a Prerequisite or Credit.
For example the Intent of Sustainable Sites Credit 2 Development Density and Community Connectivity is: “Channel development to urban areas with existing infrastructure, protect greenfields, and preserve habitat and natural resources.” The Requirements to achieve this Intent include: Construct or renovate building on a previously developed site, either in a community with a specified minimum density (Credit 2.1), or within a residential neighborhood with a minimum density and local community services (Credit 2.2).
Implications for landscape, site, and garden: This credit encourages concentration of new development within areas of existing development. The intent is to reduce the need to construct new infrastructure, and to protect greenfields, and preserve habitat and natural resources. Care should be taken however – by municipalities and higher levels of government and by developers – to protect urban and suburban stream and upland ecological corridors and significant natural areas. As development expands it tends to engulf open space areas, but these remnant natural areas, now surrounded by development, may continue to function as plant and wildlife habitat. Infill development should not sever ecological corridors, nor eat away at the edges of natural areas to the extent that the habitat or special natural features of the area are compromised.