Hamilton's neighbourhoods with the lowest incomes and poorest air quality need more trees, says a public interest group at McMaster University. And it wants the city to help make it happen.

Ontario Public Interest Group (OPIRG) McMaster knocked on doors in the Keith neighbourhood this year, signing up residents to take part in a city program that offers free trees for people's front yards.

Next year, OPIRG McMaster wants to hit more neighbourhoods, and it wants the city's help.

"We're hoping to get a partnership between the city forestry department and OPIRG McMaster," said Jonathan Valencia, the OPIRG group's air quality co-ordinator. Valencia made a presentation to the city's public works committee on Tuesday.

A formal partnership with the city would help the process move faster, Valencia said. The group would also like some money to hire two students to knock on doors in whatever neighbourhoods are chosen next year.

The OPIRG McMaster Street Tree Project began earlier this year. Using local mobile monitoring data from Dr. Denis Corr, organizers chose a neighbourhood that could benefit from better air quality. It chose the Keith neighbourhood.

Throughout May and June, 53 new trees were planted on road allowances in the Keith neighbourhood. Valencia, who did the door knocking, said residents were "very excited about it," he said.

"Overall, they were very receptive."

The city began offering its street tree program in 2004, said Mike McNamara, the city's manager of forestry and horticulture.

Through the program, residents who qualify can have a tree planted for free on the road allowance in front of their homes. The city spent about $1.5 million on the program last year and planted about 5,600 trees, McNamara said.

To qualify, residents must have adequate space between the sidewalk and their property line, and an area free of hydro wires or underground utility lines.

The city has the capacity to plant more trees through the program, McNamara said.

"Anything that promotes tree planting and identifies areas where we can add more public trees, we're fine with it."

Public trees not only beautify a neighbourhood, Valencia said. They also mean cleaner air and, eventually, better health.