Foresters ask help for Franklin Park's woods

The forests of Franklin Park, the most extensive woodlands in Boston, are in danger of losing the majestic canopy of northern red, black, and scarlet oak trees that dominate hundreds of acres of the park, according to foresters who were hired to assess the health of the park's woods.

Hundreds of oaks will die within the next half-century, the foresters estimated.

Many of the trees are 150 to 200 years old, and though oaks can live to more than 300 years in the best environmental conditions, air pollution and poor soil will probably hasten their eventual demise.

Without intervention, a new generation of oaks is unlikely to thrive, the foresters said. Saplings that would replace the older population of oaks are now being crowded out, foresters said.

The invasive species, they said, include Japanese knotweed, buck thorn, and honeysuckle.

As a result, the oaks will eventually be ''replaced by smaller, weedier trees," said the forester who is leading the study, Christian Binggeli of Brookline.

''And there will be less of them, because it will be harder for the next generation of trees to grow, because of the invasive species," Binggeli said.

The foresters are compiling recommendations that could help slow the decline of the oak trees.

They are working for the Franklin Park Coalition, a group of park advocates that commissioned the study.

The recommendations, which could cost more than $1 million over the next decade, may include cutting down some oak trees that are in decline, to make room for saplings while targeting invasive growth.

The coalition recruits hundreds of volunteers to help beat back invasive growth and keep the park clean, has begun a campaign to raise the money privately.

Its leaders hope that the city, which helped pay for the study and plans to consider adopting its management plan, will also contribute funding and manpower. ''A forest of this size can't regenerate itself," said Christine Poff, the coalition's executive director.

''It needs care and attention," she said. ''It needs an annual plan of tree pruning of dead and diseased limbs. It needs plantings and tree removals."

Today the canopy is about 70 percent oak, Poff said. There are also significant stands of Eastern hemlock and white pine, she said.

Frederick Law Olmsted carved the park from existing forest, and most of the oaks have been there since before Olmsted was born. Others he planted as a buffer around the edge of the park.

Parks Commissioner Antonia Pollak praised the coalition for its work. She also said she agrees that the park's forests could use better management. But the decline of the oaks, covering 200 acres of the 525-acre park, also raises a philosophical question, she said: How much grooming is appropriate for a wilderness?

''This place does not look the same now as it did 100 years ago," she said.

''In Frederick Law Olmsted's original design," she added, ''this was supposed to be a very natural environment, an organic environment where nature does most of the work and benign neglect is how it has been managed."

Olmsted wanted to bring the countryside to Boston when he created Franklin Park in the late 19th century.

Losing the oaks would mean losing ''the sort of magnificent cathedral effect of a New England forest," said Martha Karchere, who is president of the Franklin Park Coalition.

A takeover of low-growing trees and thick stands of knotweed, a bamboo-like plant that forms dense thickets, could also make visitors feel less safe in the park, she added, which would lead to a decline in its use.

''This is an urban forest; it's not an arboretum," she said.

Binggeli said a management plan could be expensive. Removing a single tree costs about $1,000, and pruning a tree costs about $500, he said. But some kind of management plan will be necessary, he said, if only to make sure the forest is safe as the oaks age and die.

The coalition will hold a meeting to discuss proposals for managing Franklin Park's forests from 10 a.m. to noon on Saturday, at the golf clubhouse at the park.