Trees Count! Boroughs
Citywide, the 2005-2006 census showed that our tree population grew by almost 19% since the last count. A breakdown by borough gives greater detail on the distribution, composition, and condition of our street trees.
The borough with the largest increase in trees counted between the two census efforts is Staten Island (32.5%), followed by Brooklyn (27%) and the Bronx (25%).
|Bronx (% of population)|
|Brooklyn (% of population)|
|Manhattan (% of population)|
|Queens (% of population)|
|Staten Island (% of population)|
Species. London planetree may be the most common species citywide, but it is number one only in Brooklyn (23.6%). In the Bronx and Manhattan, honeylocust is the most plentiful street tree (12.9% and 23.3% respectively), while in Queens the honor still goes to the Norway maple (18.3%). The top five street tree species in each borough are shown in the charts to the left.
Diversity. The more species comprise a population, the less impact pests and diseases can have on the health and vitality of the whole population. A population that lacks species diversity is termed a monoculture. A general rule of thumb when measuring diversity is to assemble a population with no greater than 10% of any species. Another measure of diversity is the extent to which a single species dominates a population. In general, no one species should exceed 25% of a population. By this measure, Brooklyn (London planetree), Manhattan (honeylocust), and Staten Island (Callery pear) show significant dominance by the most plentiful species.
Condition. Just over 90% of the trees were rated in good to excellent condition, with the remaining trees judged to be in poor condition (8.3%) or dead (1.4%). Staten Island has the highest number of trees in good and excellent condition (94%), with Brooklyn (91%) and Queens (90%) close behind. The Bronx had the highest number of trees in poor and dead categories (12%), followed by Manhattan (11.3%) and Queens (10%).
Conflicts. Overhead wires are the predominant urban infrastructure that conflict with trees in all neighborhoods in New York City with the exception of Manhattan. More than 35% of the City’s street trees are growing under wires. Other urban conflicts common to street trees are listed below.
Preliminary Management Observations. With the data from the census, there are a few key insights that have begun to emerge that will help us as we go forward:
- London planetree is our most important species and should always have some representation in our tree population;
- Almost 31% of our street tree species are susceptible to the Asian Longhorned beetle and our planting practices need to continue to strive for increased diversity, and reduced susceptibility to pests and diseases;
- Large, canopy trees confer the most benefits and we need to continue to focus on planting large tree species that will successfully mature.
|Borough||Damaged Sidewalks||Canopy Debirs||Choking Wires||Close Paving||Choking Grate||Tree Lights||Electric Outlet|
Tree Benefits. The value of the street trees in each borough can be quantified in terms of the amount of air pollution removed, emissions avoided, stormwater runoff intercepted, and energy saved. In addition, street trees increase property values. The dollar value of the trees in each borough are shown below (in 000s).
Tree Benefits Details (in 000s)
|Borough||Energy||CO2||Air Quality||Stormwater||Property Values||Total|
- Mayor Bloomberg’s vision for a greener, greater New York City includes the following programs to enhance our urban forest infrastructure:
- $40 million in total funding to fix over 20,000 sidewalks that are severely damaged by tree roots in a way that promotes tree and sidewalk longevity.
- $2 million each year to remove stumps as part of the new tree planting process.