Greening cities, Portland Oregon

Pearl District Portland has had a strong focus on greening - rooves, walls and lots of street tress

Greening...: (Media / Greening America's Cities: Part I); A White House Policy Briefing on ideas and initiatives to green America's cities. January 18, 2011.
Greening...: (Media / Greening America's Cities: Part II); Greening America's Cities, A White House Policy Briefing on ideas and initiatives to green
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Oregon...: (Media / Oregon Sustainability Center Designing Sustainability); Oregon Sustainability Center - Net Zero Energy
Portland State University Green Building
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