4. Goal: Green Infrastructure
Preserve natural areas and features that are ecologically unusual or environmentally sensitive. Preserve and enhance a diversity of plant and animal species in self-sustaining concentrations. Increase and conserve forests and slow the growth of impervious surface.
Source: Montgomery County Planning Department
Forests provide habitat for the plants and animals that inhabit our region, including rarer species that feed, nest, or rest in wooded areas. Forests also play a big role in moderating climate by lowering the temperature in summer by shading the soil and paved areas so that heat does not build up.
Forests stabilize the water supply. Leaves and branches retain rainwater, reducing the amount of runoff that must be treated and channeled to storm drains. The forest floor acts like a sponge, soaking up rainwater, filtering it and gradually releasing it to the groundwater and to streams.
Forests have a significant effect on air quality and global warming. Forests consume carbon dioxide and release oxygen, holding carbon in their wood. When burned, wood releases that CO2 as carbon. Even in decay, the carbon in the leaves and rotting wood are taken up by new trees and other plants, further reducing the potential for global warming. When forests are destroyed, large amounts of carbon are released into the atmosphere.
An ideal tree canopy is 40 percent 1 . While we do not have an accurate measure of tree canopy for Montgomery County, we can measure our forest cover. Continued development has reduced our forest cover to below that 40-percent ideal, but we may meet or exceed that goal in tree canopy.
Conversely, impervious surface – paved surfaces and buildings – causes rainwater to run off directly to streams and stormwater management ponds, carrying dirt and pollutants. We catch some of those pollutants through stormwater management structures such as ponds and sand filters, but even the best systems do not remove as many pollutants as natural forest canopy and forest floor.
[back to top]
