Grow Boston Greener, a collaborative effort between the City of Boston and Boston's Urban Forest Coalition (BUFC), is continuing its quest to expand the city's tree canopy by planting 100,000 new trees by the year 2020. A special focus is being placed on parts of Dorchester and other neighborhoods where trees are sparse and the canopy is unevenly spread.

"We're trying to even out who has access to the canopy," said Gretchen Folk, a project coordinator at Earth Works Boston, a member organization of BUFC. "We realize we kind of sound like tree huggers, but there are clear benefits to trees - a cooler city, a happier city, people heal faster and drive slower." Research has even shown that girls do better in science in areas with more prolific tree canopies, she added.

Boston's canopy presently covers 29 percent of the city, according to a BUFC survey, and Grow Boston Greener hopes to bring that ratio closer to 35 percent. Throughout Dorchester, the canopy ranges from 18 percent in the north to 32 percent in the south.

Last year a thousand trees were planted in the city and 2008 has seen new programs to promote community involvement and ramp up the planting and growing process. Folk said they are currently on track to have another 1,000 trees planted by April - the goal for this year is 3,000.

Twenty percent of Boston's new trees will go in public areas such as city schoolyards, parks, and streets, Folk said, leaving another 80,000 trees to be stewarded by private residents. That means trees "in every yard, for every homeowner or tenant willing to house one," she said.

Tree workshops will be held in the neighborhood this spring to introduce potential growers to the benefits of trees, how to pick the right tree and site, and how to plant and care for a new tree. Participants leave with a free tree and the "empowerment to plant your own tree," Folk said.

DEC will be sponsoring a workshop on April 3 from 6 to 8 p.m. at the Viet-AID community center and the Ashmont-Adams Neighborhood Association will hold another on April 7 from 7 to 9 p.m. at the Plasterers' Union Hall on Fredericka Street.

Boston tree parties will be held at area parks, playgrounds and schools to get neighbors involved and boost the numbers, planting 50 to 100 trees at each site. A two-day event is scheduled for April 24 and 25 at Harambee Park at Franklin Field and another day of planting will take place April 26 at the Boston Nature Center in Mattapan.

Grow Boston Greener is also appointing tree captains as neighborhood organizers to recruit stewards and provide training on selection, siting, planting, and care.

"We're really trying to build connections to people as opposed to just being about the trees," Folk said. "That's beautiful and that's part of us," she said of an urban tree canopy, but the project is also about building relationships between people who will be affected by the cleaner air and quality of life.

For more information visit growbostongreener.org or contact Gretchen Folk at 617-442-1059.