Like a child, a puppy, or a kitten, saplings need to be given attention so they grow up into strong, healthy trees. Ithacans who have a notion they might want to help raise a little honey locust or sugar maple are in luck: It’s that time of year when the city and the Cornell Cooperative Extension are looking for volunteers for their Citizen Pruner program.
Citizen pruners begin their work in May and the crew meets up twice a week through October. There’s lots of pruning to do in the city limits.
Ithaca is a “very well-treed city,” according to Prof. Nina Bassuk, director of Cornell’s Urban Horticulture Institute and chair of the city’s Shade Tree advisory committee.
“We have 11,000 street trees between the sidewalk and curb, with probably 95-percent stocking of all spaces that could be filled,” Bassuk said. “We have the responsibility of protecting those trees, particularly getting the young trees off to a good start.”
Since Ithaca is so well-treed, most of the new plantings are replacement trees for the 60 or so the city must take down every year. Most of those to go are Norway or silver maples, which are replaced with something different, according to city forester Jeanne Grace.
“Silver maples grow fast, so they were very popular,” Grace said. “They get very big, but they’re very weak-wooded and prone to losing branches in storms. A lot of the big old ones we have are not in great condition. Norway maples aren’t native, and they’re also invasive, which means they seed out into natural areas and crowd out the native stuff. They’re also notorious for lifting up sidewalks.”
Norway maples once accounted for a third of the city tree population, according to Bassuk, a proportion which is now down to about one-eighth. There are 190 species of trees in the city, Bassuk notes, the rarest being two pawpaw trees on Tioga Street in Fall Creek. The pawpaw (Asimina triloba) is native to temperate North American regions with the northern edge of its range reaching into the Southern Tier and it is related to tropical fruit species.
Grace said the city strives for a diversity of new trees, though she does say the honey locust is a “quintessentially all-around street tree” that can thrive in areas with poor soil quality and not much water. Ginkgo, sugar and red maples, varieties of oak, horse chestnuts, and Kentucky coffee trees are some other species that are planted as replacements.
Volunteers will learn to use the tools and where to make the proper cut for “structural pruning.”
“That’s when you look for what you need to correct,” Grace said. “A common problem is co-dominant stems. In most varieties you want one central leader and branches coming off that. Sometimes that union where two or three stems meet is where a tree could fail.”
Crossing branches and keeping limbs from growing out at too low a point—a particular problem for street trees—are other issues that Grace’s volunteer crew watches over. They also do some landscape shrub pruning in the parks.
One prerequisite for volunteer pruners is that they accept their feet must stay on the ground. High-up cherry-picker trimming work is taken care of by the public works department.
“We get some people who are so enthusiastic, they say ‘Can I jump up on that branch?’” Grace said. “We do have pole tools so we can do some overhead pruning, which most people don’t have at home, so it’s cool they can use it and learn some new equipment.”
Grace scouts areas of the city that need work, then puts out a call to the citizen pruners. They meet twice a week, on Monday nights and Tuesday mornings, for two hours or so. She sends an email the week before with a meeting place and a range along which the crew will be working, so people can come when they can and catch up to the group. As a bonus, volunteers sometimes discover new nooks of the city, Grace said.
“Even people who have lived in Ithaca a long time, when I say we need to work up on say, Crescent Place, they’ll say ‘Where the heck is that?’”
Two introductory pruning classes open to the public and prospective volunteers still remain on April 20 and 27. Those interested in the classes and volunteering can call the Cooperative Extension at 607-272-2292. •