Is it Native? Plant Databases.

These databases will help you find plants native to Westchester:

Metropolitan Flora Project (Brooklyn Botanic Garden)
Westchester Native Plants (Native Plant Center)
PLANTS Database (US Department of Agriculture)

Forests are the best land use for sustaining water quality.

From the USDA Forest Service Northeast Area Watershed Program:

Clean water is one of our most important and valuable forest products. In urban areas, trees and forests reduce storm water runoff, cool the air, and provide critical refuge for fish and wildlife. Forests also help clean the air we breathe.

By filtering pollutants from air and water, storing water and nutrients, protecting soils, flood plains, and streams, and providing aesthetic and other human needs, forests bring significant benefits to our lands, waters, and communities. People depend on healthy and well-managed forest lands. Over 50 million people depend on northeastern forests, in part, to protect their water supplies.

Also see the Northeast Area’s Publications.

The Watershed.

“[A watershed is] that area of land, a bounded hydrologic system, within which all living things are inextricably linked by their common water course and where, as humans settled, simple logic demanded that they become part of a community.”

— John Wesley Powell

Online training in watershed management from the Environmental Protection Agency.