The Department of Horticulture and Landscape Architecture at Colorado State has indentified five particular species of plant that work well in semi-arid climates for green roofs.
Energy Daily reports that "Previous research on species that can survive and thrive on extensive green roofs has shown that succulents outperform most non-succulents."
Blue grama and hardy ice plant weathered the test best, outperforming other succulents.
The study is being conducted on the roof of the Colorado headquarters for the Environmental Protection Agency, a LEED-certified office building.
From the EPA's website:
"While installing green roofs has been gaining in popularity in temperate areas marked by relatively ample rainfall such as Europe (green roofs are particularly popular in Germany) and the Northeastern U.S., developers, architects, and building managers have much less experience installing them in places with low rainfall and the solar extremes presented by high altitudes. EPA's green roof is the first of its kind in the state of Colorado."
FULL STORY: Five Standout Species for Extensive Green Roofs

Analysis: Cybertruck Fatality Rate Far Exceeds That of Ford Pinto
The Tesla Cybertruck was recalled seven times last year.

National Parks Layoffs Will Cause Communities to Lose Billions
Thousands of essential park workers were laid off this week, just before the busy spring break season.

Retro-silient?: America’s First “Eco-burb,” The Woodlands Turns 50
A master-planned community north of Houston offers lessons on green infrastructure and resilient design, but falls short of its founder’s lofty affordability and walkability goals.

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Analysis: Cybertruck Fatality Rate Far Exceeds That of Ford Pinto
The Tesla Cybertruck was recalled seven times last year.

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