The Pennsylvania Horticultural Society recently launched its third “More Trees Please” fundraising campaign — a campaign desperately needed to keep the city Tree Tender crews planting saplings and growing our green canopy.
The campaign undoubtedly will help Philadelphia strengthen its urban forest and reverse long-standing environmental inequities.
Yet despite these laudable efforts and those of the city’s Tree Philly programs, our city continues to lose tree canopy faster than we can replant it, even prior to the current crisis.
Per the Philadelphia Tree Canopy Assessment Report released in December 2019, between 2008 and 2018, we lost approximately 6% of our urban tree canopy.
The report states that much of the canopy loss has occurred in park space — this loss will likely accelerate due to ash trees succumbing to the Emerald Ash Borer and weakened by the spotted lanternfly, losses from increased storm severity as our climate becomes hotter and wetter.
Then there’s street tree attrition due to development-related construction. The reduced canopy coverage has largely coincided with the only period in decades when the city has gained population and experienced an increase in construction activity.
With private, city, state, federal and philanthropic resources further stretched due to COVID-19, we must think creatively to grow our city’s tree canopy with what are sure to be limited resources and to find common purpose among the many city agencies, non-profits, businesses and residents working towards our ultimate goal of a 30% canopy cover. The city’s work bringing leaders together towards developing an Urban Forest Plan is an impressive start.
However, there are many things we can do right now.
Nearly 80% of all parcels in the city are zoned residential — this provides an enormous opportunity by which new street trees can be included in new development or added subsequently to accompany existing structures.
Increasingly, developers are proposing large, multi-unit residential or mixed-use developments that include significant frontages, ripe for street trees. Yet we find that in recent years, these developments typically have not yielded the anticipated street trees, and in fact are often completely bereft of them. In part this is because street trees are not regarded as necessary infrastructure throughout the design, permitting and construction process to the same degree as other city mandated design elements. While the city code has detailed requirements for trees, and often developer intentions are good, poor planning results in tree removal, non-ideal species selection, and logistical barriers when planting time ultimately comes. A detailed forest plan at the start of development projects could help ensure installation of important tree infrastructure.
As for owners of existing structures, the resident or business owner has three legal options to obtain a street tree:
- Request a tree from Parks and Recreation, with an expected wait time in excess of one year should funds be available;
- Request a tree through the PHS Program whose volunteer Tree Tenders will plant a tree, typically within six months — again, subject to adequate city-wide funding, with priority for trees in areas of the city that have low canopy coverage, a history of being economically disadvantaged and are populated by historically disadvantaged and discriminated against communities;
- Or, the fastest route: The property owner independently obtaining a permit to have a tree planted by a city-approved contractor
For this third, quickest option, the city can decrease the financial entry threshold of purchasing a street tree by simply relaxing its tree planting size rules for those planted via the private sector.
The city requires trees planted of 2” or greater diameter at breast height, to ostensibly ensure higher survivability rates and be better able to withstand vandalism and other mechanical injuries such as vehicle door impacts. But the science on this is mixed, as younger trees have to spend less time and energy reconstituting their root systems, following transplantation.
What is certain is that, per price quotes from local tree companies, larger trees in ball and burlap cost more to transport and plant ($500+) than container trees that can be transported and handled without heavy machinery, which cost $200 between $300 per tree, if planted professionally or only $100-$150 if planted by volunteer Tree Tenders. This represents a significant cost barrier to tree ownership, particularly in Philadelphia, a city with historically high poverty rates, even before the pandemic.
Anecdotally, we have spoken to multiple prospective tree purchasers who have balked at the high costs and instead elected to wait for “free trees” from PHS or the city.
Once a property owner chooses to plant, there are myriad other decisions made that determine how much their tree will help us expand our canopy.
For one, trees of the same age at planting, at the same price point, have variable growth rates and branch habitat. Growth depends on species and cultivated characteristics as well as other factors. For example, a tree cultivated for a columnar shape might only have a 15’ diameter spread at maturity but for the same cost, a non-columnar tree of the same species could potentially have more than double the canopy spread. Granted, trees with greater crown diameters are not appropriate for all situations, but should be accommodated where feasible. Buf if you go down that green path, know the tree will require increased pruning, a task that volunteer PHS Tree Tenders, who have earned the Advanced Tree Tender Certificate, are eager to help with.
While we must do a better job of preserving the city’s existing street trees through other policy changes and improved aftercare, as recently outlined by various members of the PHS Tree Tender Steering Committee, there are a lot of ways homeowners, utility companies and the development community can contribute to the canopy. Remember, fall is the season of trees so donate what you can, plant if you want and don’t forget to take care of the saplings in your life.
Marcus Ferreira and Sarah Anton are Co-Chairs of the Pennsylvania Horticultural Society (PHS) Tree Tender Steering Committee in addition to serving in leadership roles in the Southwest Center City and Passyunk Square neighborhoods, respectively.