Is Mountain View losing trees from breakneck development, or is the town planting enough younger trees to replenish them? It's sort of like asking if a cup is half empty or half full -- it depends on who you ask.
A new draft report by the city's Forestry Division finds that nearly 2,400 trees have been chopped down across town over the last three years. On the bright side, city arborists report that they are replanting 60 percent more new trees and saplings compared to what's been removed.
Yet tree advocates in Mountain View remain skeptical. Not all trees are equal, said Katherine Naegele, an arborist with the Mountain View Tree nonprofit who previously served on the city's Urban Forestry Board.
While a higher tree count might seem like proof of success, it could also mean that a developer ripped out healthy mature trees only to be replace them with saplings from the nursery, she said. After winning their approvals, many developers often pick non-native trees and then plant them too closely together or in spaces that can't support their roots, she said. These trees will end up dying, but the city's tree count will still portray it as a net increase, she said.
"It might seem like we're getting this lush new tree cover, but actually we're just counting the number of trunks to satisfy the city's policies," Naegele said. "I would rather see someone plant two coast live oaks rather than 100 myrtles."
The city's policies for protecting heritage trees have come under new scrutiny in recent days following a community outcry against plans to take down a grove of redwoods off Sierra Avenue. City officials ultimately denied permits to remove the trees, yet the episode still left many residents with the feeling that the city has a "double standard" for which trees are protected. The city does have two different tracks for granting these permits, but that split process confuses many residents, said Parks & Recreation Commissioner Paul Hepfer.
For a basic tree removal -- such as a homeowner seeking to chop down a tree -- that goes to the city's Urban Forestry Division under the Community Services Department. If a project decision is appealed, then it goes before the Parks & Recreation Commission for a public hearing. Since July 2016, the Forestry Division has logged requests to remove about 430 trees, about half of which were approved.
The majority of tree removals are attached to development projects. When trees need to be removed as part of a larger project -- say, to construct a new office building -- that decision goes to the city planning division instead. Heritage tree removals are typically packaged into the larger set of building permits approved either by city staff or the City Council. In massive projects, advocates say the fate of the trees is often given secondary treatment when compared to parking, transportation and other considerations. To take one example, 247 trees were removed as part of a LinkedIn office project at 700 E. Middlefield Road, and the developer was required to replant only 53 trees.
The Voice filed a public records request with the city asking for totals of how many trees were removed throughout the city based on development dating back to 2010. City officials identified more than 200 projects that involved tree removals, but they could not provide specific numbers or details on most of those projects except by going through individual development approvals by hand. The city began tabulating trees removals from development starting in 2015, according to Forestry Division officials. A data map of the tree removals can be found here.
Given the brisk pace of development, it seems reasonable to be concerned that matures trees are being treated as an afterthought, Hepfer said.
"I don't think every heritage tree needs to remain just because it's a heritage tree, but it's important to maintain a tree canopy," he said. "We're at a point right now where I'm afraid because of how fast development is being approved. What we lose, we might not get that back."
It is tricky to say whether the city's tree canopy is dwindling, said Brady Ruebusch, a city analyst involved in the heritage tree program. Every few years, a city team gleans satellite imagery to get a bird's-eye view of the citywide tree canopy, which is available online. Eventually, city officials should be able to determine spots where tree coverage is depleted, Ruebusch said.
The city has set a goal to increase its total tree canopy by about a third, or about 11,000 trees, by 2020. He believes that is achievable, but he acknowledged that trees take a long time to fully grow, so gauging success might take a while.
"We might not know the potential of all of this for 10 to 15 years," he said.