Portland area communities look to strengthen "green infrastructure"
Street trees gain stature as awareness of their air-cleaning, water-absorbing and aesthetic benefits grows
Robin Franzen, The Oregonian
In a world of people and plants, trees stand out as solid citizens. They clean and cool the air. They slow water runoff. They make neighborhoods feel like neighborhoods.
During the past century, however, humans felled many of the trees that once greened the Portland region and soaked up its abundant rainfall. The gray result: concrete mega-projects such as Portland's $1.4 billion Big Pipe, tunneling alongside the Willamette River to control millions of gallons of storm water that run off the unforested urban landscape each year.
Yet, like a leaf starting to unfurl, tree-thinking is changing. Recognizing that they can help combat climate change, and ultimately save society billions of dollars in combination with more conventional "gray" infrastructure, jurisdictions are stepping up to save existing stands and replant trees in urban areas.
This summer, Portland, known nationally for its well-treed image, launches "Grey to Green," a five-year, $50 million, green-up-the-city initiative that includes planting 83,000 trees -- 50,000 of them along streets, increasing the city's street-tree inventory by about one-fourth.
