Surprise, surprise: Portland made the American Forests list of the top 10 U.S. cities for urban trees.

The forest conservation group recognized the city for turning a former freeway into the Tom McCall Waterfront Park, for depaving parking lots and filling them with greenery, for maintaining the 5,100 acres of Forest Park and the hundreds of species of trees and shrubs at Hoyt Arboretum. Unlike most cities in the country, the group found, Portland’s urban canopy has been growing in recent years.

The rankings were based based on public involvement in the urban forest, public access to trees and green spaces, city planning, knowledge and management of the urban forest, as well as the overall health of city trees. The top 10 cities are: Austin, Charlotte, Denver, Milwaukee, Minneapolis, New York, Sacramento, Seattle and Washington, D.C.

Seattle got points for preserving an old growth forest, for turning a crude oil plant into Gas Works Park, and for preserving hundreds of species at Green Lake Park. The city of Seattle did an analysis of its urban forest to determine where trees can be planted and which species would be best.

By comparison, Portland’s urban forest canopy covers about 30 percent of the city while Seattle’s covers 23 percent, according to the American Forests rankings. But Seattle is home to an estimated 4.35 million trees to Portland’s 1.4 million.

The report says Portland’s trees cost around $6.5 million a year to maintain, but they provide nearly $27 million in benefits – including the removal of 2 million pounds of pollutants and 53 million pounds of carbon from the air.

For more context on the virtues of urban trees, check out the city of Portland’s arsenal of research. Studies show city trees attract tourists, spur consumer spending, raise property values, reduce heating and cooling costs in houses and buildings, lower greenhouse gas levels and mitigate storm water pollution.

They’ve even been tied to lower crime rates.

Of course, they can also clog up the sewers in the rainy season, which leads to flooded streets. Then again, some say the trees aren’t the ones to blame for that.