With the growing threat of climate change, New York City is implementing actions and policies to mitigate and reduce its impact. The city’s sustainability plan, “PlaNYC: Getting Sustainability Done,” highlights vital areas that need to be addressed, such as protecting from flood events, promoting clean energy in buildings, expanding open spaces and parks, as well as an emphasis on the importance of mitigating extreme heat. With the collaboration of community-based organizations, the city is leading a significant tree-planting initiative, as outlined in Local Law 1065 (LL 1065). The city has set the goal of planting thousands of trees across the city to support efforts to improve air quality. Enacted in November 2023, LL 1065 lays the groundwork for the city’s urban forest objectives and aims to expand the city’s canopy coverage from the current 22% to 30% as recommended by the NYC Urban Forest Agenda.
In its fourth regional plan, RPA underscores the pivotal role of trees, open spaces, parks, and green infrastructure in addressing climate change, particularly in mitigating the hazards associated with high temperatures and urban heat islands (UHI). The plan outlines three critical environmental goals for the region: first, institutionalizing greening initiatives and relief programs at the community level; second, mandating major urban projects to incorporate green elements; and third, employing pilot programs to assess the impact of natural approaches and develop community-based solutions. Furthermore, RPA publicly supported LL 1065 and the proposed city-wide urban forest master plan, emphasizing the necessity of strict timelines to ensure effective implementation and highlighting the importance of prioritizing environmental justice communities historically in environmental justice communities.
Under LL 1065, the city is mandated to create an urban forest master plan to be submitted by July 31, 2024, which would be updated every decade. This comprehensive plan will examine the factors influencing changes in canopy coverage, offering strategic recommendations to prevent future canopy loss and promote tree canopy growth. Additionally, the plan requires the development of outreach and education programs to inform property owners about best practices for protecting existing trees and planting new ones.
LL 1065 has laid a strong foundation to increase canopy coverage, support the city’s efforts in combating the effects of climate change, and reach the city’s sustainability goals. However, its success depends on various critical factors like setting specific targets, implementing effective enforcement mechanisms, fostering cooperation among city agencies, and investing in historically underinvested neighborhoods and communities.
Local Law 1065 stands as a milestone of the city’s tree-planting efforts, aligning with its environmental objectives and building upon the foundation laid by the Million Trees NYC Program (MTNYC) initiated in 2007. The MTNYC set out an ambitious goal of planting 1 million trees across the city’s five boroughs, with a budget totaling up to $365 million allocated over several fiscal years. The program successfully reached its goal of planting 1 million trees ahead of schedule, completing the project in under 10 years. Looking back, however, prioritizing the overall quantity of trees planted might not have been the most effective strategy. It could have been more impactful if there was an effort to prioritize planting trees in locations where their environmental and community impact would be most substantial.
While LL 1065 aims to achieve ambitious and important environmental goals, it would benefit from a more detailed plan outlining the distribution of new trees across streets, parks, open areas, and various neighborhoods. A more comprehensive approach to tree planting and distribution could ensure that the benefits of urban forestry are accessible to all communities, especially those most in need. LL 1065 should learn from past initiatives’ mistakes and prioritize a more precise and equitable allocation of trees rather than just the total canopy coverage goal, especially among environmental justice communities. A closer examination of existing tree and canopy coverage data in New York City, taking Brooklyn as a case study, reveals discrepancies in the current distribution of trees, indicating a need for further attention and action to ensure the successful implementation of the law’s objectives and the city’s environmental justice goals.
This research offers a new approach to urban forestry building on LL 1065, existing policies, and the legacy of tree planting initiatives in NYC. The following sections will cover the current state of New York City trees and canopy coverage distribution, and offer recommendations for developing new urban forest zones (UFZ) to support the implementation of LL 1065 and its historic environmental goals.
As a result of climate change, New York City experiences extreme weather conditions, including extreme heat. An analysis of the UHI severity in Brooklyn was conducted using data from 2019. The findings indicate that the most severe UHI effect is concentrated in Brooklyn’s northern, northeastern, and western neighborhoods, particularly Sunset Park. The area impacted by UHI covers 20,410 acres, representing approximately 46% of Brooklyn’s total land coverage. It is important to note that the analysis and maps only depict UHI severity and not land surface temperatures, extreme heat events, or other temperature variations.
![Urban Heat Island Severity](https://img.imageboss.me/general/width/300/quality:80/latest/Urban-Heat-Island-Severity.png?bossToken=9b6b8f30a839bc8d9a6e06071c4ef4d092c1e5ceaafb3242c7f573186b746f52 171w, https://img.imageboss.me/general/width/600/quality:80/latest/Urban-Heat-Island-Severity.png?bossToken=72f220cc81bb03377929b81821e2920b4fff51f88018fd2a0851115b9af5c379 343w, https://img.imageboss.me/general/width/900/quality:80/latest/Urban-Heat-Island-Severity.png?bossToken=c9cc13e9b381fe27b493d35cf387545d90074dac77e2e5981fbc3e3dfaa51f44 514w, https://img.imageboss.me/general/width/1200/quality:80/latest/Urban-Heat-Island-Severity.png?bossToken=1767744513632ef1fa04aaba663aadff2847dc1179baa3dbe351e29cef080784 686w, https://img.imageboss.me/general/width/1500/quality:80/latest/Urban-Heat-Island-Severity.png?bossToken=afd627f6403e40b5868655a35f89ad349fcc12835defdc0705046a8ebf6a6e7e 857w, https://img.imageboss.me/general/width/1800/quality:80/latest/Urban-Heat-Island-Severity.png?bossToken=9f43cf0ddc209b8c2c918223f838ac05d494f132f61176937cc75c204893d8df 1029w, https://img.imageboss.me/general/width/2100/quality:80/latest/Urban-Heat-Island-Severity.png?bossToken=754690e076affc9d7fa24764f95d88e1b9f9d427ee8eac7d4876b53b483bece9 1200w, https://img.imageboss.me/general/width/2400/quality:80/latest/Urban-Heat-Island-Severity.png?bossToken=b5794ee54ba2cf84d0ffb704186f8843da5d6ea73d0d6de43d69675abc0f06b9 1371w, https://img.imageboss.me/general/width/2700/quality:80/latest/Urban-Heat-Island-Severity.png?bossToken=e3cb4534c639d027afbeefbcd20e24024e753d42f70fb14517703f3d9606f706 1543w)
Source: The Trust for Public Land. Urban Heat Island Severity for U.S. Cities (2019)
Different methods can be used to evaluate New York City’s total canopy coverage and its status across neighborhoods. This research utilized two datasets: Google’s Environmental Insights Explorer (EIE) and the city’s Tree Canopy Change from 2010 to 2017. Both data sets estimate canopy coverage for a similar period. Comparing the two provides a comprehensive and nuanced understanding of the current state of tree coverage change in NYC.
According to data obtained from Google EIE spanning 2014 to 2022, NYC’s total tree coverage extends across approximately 44,000 acres, constituting 23% of the city’s area. This suggests that progress toward the city’s goal of achieving 30% canopy coverage is underway. Figure 2 illustrates the percentage of canopy coverage by census tract across NYC, which includes parks, open spaces, and street trees.
Based on the 2015 street tree census, the number of street trees in each of the five boroughs in NYC varies. Queens has the highest number of street trees, totaling 237,974, followed by Brooklyn with 169,744, Staten Island with 101,443, the Bronx with 80,585, and Manhattan with 62,427. Combined, these figures culminate in 652,173 live street trees across the city.
![Canopy Coverage by Census Tract NYC Google EIE Large](https://img.imageboss.me/general/width/300/quality:80/work/Canopy-Coverage-by-Census-Tract-NYC-Google-EIE-Large.jpeg?bossToken=26cabd77203262a3277ec901ff7cecc72edbb271154f5b5b0196301cc6ffb71f 171w, https://img.imageboss.me/general/width/600/quality:80/work/Canopy-Coverage-by-Census-Tract-NYC-Google-EIE-Large.jpeg?bossToken=224297a9bff254a6108310d2e1f407f52190c2062f7da5c30be8ad3d7dfec42a 343w, https://img.imageboss.me/general/width/900/quality:80/work/Canopy-Coverage-by-Census-Tract-NYC-Google-EIE-Large.jpeg?bossToken=51f48a0cdc876558fa9e57f985b1fba1f73cba49e5b44efac59ec53268a1361f 514w, https://img.imageboss.me/general/width/1200/quality:80/work/Canopy-Coverage-by-Census-Tract-NYC-Google-EIE-Large.jpeg?bossToken=29d99284ff2d21670a9039272b24becb98dddfdceb749df68a62282ffb63dfbc 686w, https://img.imageboss.me/general/width/1500/quality:80/work/Canopy-Coverage-by-Census-Tract-NYC-Google-EIE-Large.jpeg?bossToken=e8b5950931c2752fb9e8adbbc53f8e5d010f0c7474272a061fb94039757ad5c3 857w, https://img.imageboss.me/general/width/1800/quality:80/work/Canopy-Coverage-by-Census-Tract-NYC-Google-EIE-Large.jpeg?bossToken=d85a7de6dc96863925458da77d7e5996e150d2a566ef847c25090c4f6233cded 1029w, https://img.imageboss.me/general/width/2100/quality:80/work/Canopy-Coverage-by-Census-Tract-NYC-Google-EIE-Large.jpeg?bossToken=4b1133b5af5b6334006d969f72a980cafe982bd6e1bbcf4ecb7c0916fd04308d 1200w, https://img.imageboss.me/general/width/2400/quality:80/work/Canopy-Coverage-by-Census-Tract-NYC-Google-EIE-Large.jpeg?bossToken=141ec321d39ca2597d2c1e07cd387e645ff2a734c7314f63bb62bde94a50e8be 1371w, https://img.imageboss.me/general/width/2700/quality:80/work/Canopy-Coverage-by-Census-Tract-NYC-Google-EIE-Large.jpeg?bossToken=06a617489463ffd96ade1d3c0b047f7ab438866945dc7b6ed2ecf191388c8729 1543w)
Figure 2: Percentage of Canopy Coverage, NYC
Although overall canopy coverage is around 23%, focusing solely on streets presents a different perspective. The analysis utilizes the Tree Canopy Change dataset spanning from 2010 to 2017, with a specific emphasis on the evaluation of street canopy coverage. Notably, the mapping process deliberately excluded parks, open spaces, and airports, ensuring a concentrated focus on street-level canopy coverage. This approach is crucial to get a nuanced understanding of urban landscapes, particularly in enhancing factors such as walkability and cycling.
The City’s evaluation of canopy change between 2010 and 2017 highlights shifts in canopy coverage and is divided into three categories: No Change in canopy, canopy Gain, and Loss of canopy. For instance, some trees may have experienced canopy growth on a particular block or street, while others may have remained unchanged or seen partial canopy loss. Canopy growth may have resulted from tree growth or new tree planting. In contrast, canopy loss could be due to tree death or the effects of diseases leading to canopy loss.
The analysis finds that around 64% of New York City’s street canopy remained unchanged during the period measured. The study also showed a 23% increase in canopy coverage, indicating positive growth. However, there was a 13% decrease in street canopy, indicating a reduction in coverage during the same time frame. By 2017, street canopy coverage on streets totaled about 18,367 acres, representing nearly 10% of the city’s total land area.
Analyzing Brooklyn as a case study provides insights into the current state of street trees and the potential for future development of the borough’s urban forest. With approximately 170,000 living street trees, Brooklyn’s canopy coverage presents significant opportunities. The concentration of living street trees in Brooklyn is presented in Figure 3, with white and light green indicating a low concentration and darker green symbolizing a higher number of street trees.
The study reveals that approximately 75% of street segments in Brooklyn have a canopy coverage ranging from 0% to 25%, as depicted in Figure 4. This study evaluates the canopy coverage of existing canopies along the 60-foot-wide streets of Brooklyn. In Figure 5, a street map of Brooklyn illustrates the diverse levels of canopy coverage along streets. Red indicates low coverage, and green highlights higher percentages, emphasizing the spatial distribution of urban tree canopy within the borough.
The study finds that street trees are not equally distributed across the borough, resulting in uneven canopy coverage for Brooklyn residents. This imbalance leads to environmental disparities, placing certain communities at a higher risk of exposure to UHI effects, asthma, air pollution, and other environmental hazards.
The following section outlines an alternative approach to address the uneven distribution of street trees and canopy coverage among Brooklyn’s neighborhoods. Furthermore, it presents a model that can be used to identify appropriate locations for tree planting and implement them throughout all five boroughs. Taking advantage of LL 1065 and the city’s initiative to increase canopy coverage, the model can be used as a guide and provides suggestions for fairly distributing the targeted 30% canopy coverage. This will ensure that all residents of NYC can benefit from the improved urban greenery.
![Trees hex BK 12112023](https://img.imageboss.me/general/width/300/quality:80/work/Trees-hex-BK-12112023.png?bossToken=4829fc90c12afa6057e9fc8b44d219ac6bb6db242c4968dd3624d7e4c472a4ff 171w, https://img.imageboss.me/general/width/600/quality:80/work/Trees-hex-BK-12112023.png?bossToken=860da9e989c67cfff02dabce7b76b04cee69d0c71b0d1d3097ad82837a228cd6 343w, https://img.imageboss.me/general/width/900/quality:80/work/Trees-hex-BK-12112023.png?bossToken=0ba40c3b6d9122dc337c7479375502ed1cff3005d7c4ee2c664d703a048f8d7a 514w, https://img.imageboss.me/general/width/1200/quality:80/work/Trees-hex-BK-12112023.png?bossToken=4445eb84320d321296884ebd414c28558b88389dd171f20827715bbe485e64d6 686w, https://img.imageboss.me/general/width/1500/quality:80/work/Trees-hex-BK-12112023.png?bossToken=cacf77625dcb6f18e6767c57c5c5df9cb105fb3eef248e2ec575027ebffaba01 857w, https://img.imageboss.me/general/width/1800/quality:80/work/Trees-hex-BK-12112023.png?bossToken=b96510cd21eaa09aba5e67c6096660a108d4cc6423033148d069921a22a38a04 1029w, https://img.imageboss.me/general/width/2100/quality:80/work/Trees-hex-BK-12112023.png?bossToken=d503c4f32c2b9db62c90223bac46c9e7de09cc9a39b7dd4bf9cd8a5786a3ab72 1200w, https://img.imageboss.me/general/width/2400/quality:80/work/Trees-hex-BK-12112023.png?bossToken=90dc2c5952823df6720343146cb9558df56c9c5169b672e135eb78805945270b 1371w, https://img.imageboss.me/general/width/2700/quality:80/work/Trees-hex-BK-12112023.png?bossToken=1a314cb3fb3215f86850a625ed105bebc1ae423b05f1c0e6d36e0eee1ce706ff 1543w)
Source: NYC DPR, 2017
![Percentage of Canopy Coverage on Streets Large](https://img.imageboss.me/general/width/300/quality:80/work/Percentage-of-Canopy-Coverage-on-Streets-Large.jpeg?bossToken=af1132396187376d7f2740e32d211d0e7ae20f53d4ae6360804ce5bfe53eab1b 171w, https://img.imageboss.me/general/width/600/quality:80/work/Percentage-of-Canopy-Coverage-on-Streets-Large.jpeg?bossToken=0d157de4735b5e3d0d4a2d75bb63f9783d99fc036ae1316c061c37553d92201e 343w, https://img.imageboss.me/general/width/900/quality:80/work/Percentage-of-Canopy-Coverage-on-Streets-Large.jpeg?bossToken=7fbec05a9d49609fa6e9da27d601a3875456b3e1b790254e02e7b804ced76c6c 514w, https://img.imageboss.me/general/width/1200/quality:80/work/Percentage-of-Canopy-Coverage-on-Streets-Large.jpeg?bossToken=49a9307ff66b294ccd1ab3f3d5e49e25793b19cea82b2a893f7a231bc51681eb 686w, https://img.imageboss.me/general/width/1500/quality:80/work/Percentage-of-Canopy-Coverage-on-Streets-Large.jpeg?bossToken=be58996d16a58f49a41426332f9ce360ee26ceb8d67da0b6f288a38b984b9eb8 857w, https://img.imageboss.me/general/width/1800/quality:80/work/Percentage-of-Canopy-Coverage-on-Streets-Large.jpeg?bossToken=dbe244a9c41821913f106c01fc5a0d2dfae9b01ae237122cac3465d286d7bc16 1029w, https://img.imageboss.me/general/width/2100/quality:80/work/Percentage-of-Canopy-Coverage-on-Streets-Large.jpeg?bossToken=2f20286b22b7b1475a560ec37959ce7822e02cf1ab6681392384183c79ac2094 1200w, https://img.imageboss.me/general/width/2400/quality:80/work/Percentage-of-Canopy-Coverage-on-Streets-Large.jpeg?bossToken=6b39d3ea32d0c8b1f990c48eaa89acf1d1fceb2fb573d8173114eb8564c49c59 1371w, https://img.imageboss.me/general/width/2700/quality:80/work/Percentage-of-Canopy-Coverage-on-Streets-Large.jpeg?bossToken=7c927ae94efca75103e1c4895b6f1f7d9242f2f87d4f58d713c8b65a9d5377d9 1543w)
Source: NYC OTI, 2022b, 2023
LL 1065 and its 30% canopy coverage goal mark a significant step in redefining the concept of urban greenery and reshaping the integration of urban forests into the city’s landscape. The model proposed below advocates for customizing the 30% canopy coverage goal into a site-specific action plan tailored to prioritize environmental justice communities. This approach aims to address the disparities in canopy coverage across neighborhoods and ensure equitable access to the benefits of urban forestry.
Using Brooklyn as a case study for new UFZ development, Figure 6 displays the areas most needed for UFZ development. The model uses 5 datasets comprising the final result. Each is given respective importance (weight), with those assigned a higher weight in the model having a more significant impact on the final suitability model. The final result integrates several variables, which include the number of living street trees, focusing on areas with lower tree concentrations; UHI severity; lower levels of Median Household Income from 2017 to 2021; communities at higher risk as defined by NYSERDA’s Disadvantaged Communities Index; and New York City’s land use categorization, with an emphasis on residential and mixed-use areas. This model can be expanded to other boroughs and modified by adding more variables (e.g. environmental and demographic factors).
Figure 6 maps locations in Brooklyn identified as more suitable for UFZ expansion, with high-priority areas marked in red and low-priority areas in green. This data-driven approach can inform policy decisions regarding the strategic placement of trees to address environmental equity and enhance urban greenery. Additionally, a statistical analysis was conducted on the potential development of UFZ, as depicted in Figure 7. This analysis identifies clusters of UFZ with varying suitability levels, represented by hot spots (red) or cold spots (blue) across three confidence levels (see Appendix 2 for a detailed explanation of the statistical results).
![Suitability model UFZ 121123](https://img.imageboss.me/general/width/300/quality:80/work/suitability-model-UFZ-121123.png?bossToken=ad863206c646cfc6e181a029384073538dde24b1567b85864e49757a5c0c11bd 171w, https://img.imageboss.me/general/width/600/quality:80/work/suitability-model-UFZ-121123.png?bossToken=51ceaea59b24df9be8060a72ebebe9bd7a24e815601b49cd91a5cdcc15192917 343w, https://img.imageboss.me/general/width/900/quality:80/work/suitability-model-UFZ-121123.png?bossToken=0967f1c5c6b9f0849381c569e6280be77869fb7c7b8767e01d94aa1b064d1034 514w, https://img.imageboss.me/general/width/1200/quality:80/work/suitability-model-UFZ-121123.png?bossToken=a90eda50f5a577df365046392a4c82b1fc51cedc7fb2ec6884b9e9e5bae6f847 686w, https://img.imageboss.me/general/width/1500/quality:80/work/suitability-model-UFZ-121123.png?bossToken=c046caec60b92b42aa355526807bad1fee510f1c4812546e185aaced8b59c133 857w, https://img.imageboss.me/general/width/1800/quality:80/work/suitability-model-UFZ-121123.png?bossToken=2bb963e9df21be348cf70f5a9d2ac0ff78bdd5af5ca865d6d076608ff5b3f9b8 1029w, https://img.imageboss.me/general/width/2100/quality:80/work/suitability-model-UFZ-121123.png?bossToken=ab9e8b5121435b19fd01fe2e6498da9893f3bff75631451496d6e458364692aa 1200w, https://img.imageboss.me/general/width/2400/quality:80/work/suitability-model-UFZ-121123.png?bossToken=495dc475aea3d3d851c0408dde9abcceb8edc40e4e3ab4cca681ce821560849d 1371w, https://img.imageboss.me/general/width/2700/quality:80/work/suitability-model-UFZ-121123.png?bossToken=b940cf056454cf7a7f0b963151570d8be72c891365efb447c43bb2155d4a91b2 1543w)
Source: DCP, 2023; IPUMS, NHGIS; University of Minnesota, n.d.; NYC DPR, 2017; NYSERDA, 2023; The Trust for Public Land, 2019
Aligned with the goals of LL 1065 and the sustainability objectives outlined in PlaNYC, the following recommendations aim to enhance the implementation of the 30% canopy coverage goal and ensure equitable tree and green infrastructure distribution, focusing on environmental justice communities. The recommendations center on three main areas: establishing urban forest zones, appointing an urban forest coordinator, and implementing measures to address extreme heat.
Establishing Urban Forest Zones
The first recommendation seeks to establish Urban Forest Zones (UFZ). These areas are strategic locations aimed at promoting the expansion of urban forests, with a particular focus on environmental justice communities. As shown in the maps and analysis above, these priority sites can be determined by the methodology suggested in the research, which can be expanded to more locations across the city and include additional indicators.
UFZs could follow a similar logic used in establishing Business Improvement Districts (BIDs), which are designated areas based on financial needs rather than more common boundaries such as neighborhoods or census tracts. However, in the case of UFZs, the focus would be on environmental and sustainability indicators rather than financial. The enactment of LL 1065, which mandates the development of an urban forest master plan by July 31, 2024, underscores the importance of this recommendation in providing guidelines for implementation and subsequent enforcement.
Introducing the Urban Forest Coordinator
The second recommendation proposes the establishment of a city-wide Urban Forest Coordinator position. The Urban Forest Coordinator could play a vital role in the long-term planning, strategic vision, and evaluation of urban forestry initiatives. This position could serve two primary objectives: the first is to strategically plan and develop UFZs across the city, and the second is to coordinate between different city agencies to advocate for its success. This position mirrors the Chief Public Realm Officer (CPRO) role established by Mayor Adams in February 2023. The Urban Forest Coordinator could work independently while coordinating with city agencies or be integrated into the CPRO’s office and tasked with enhancing green public spaces and UFZs.
Mitigating Urban Heat Islands
The third and final recommendation emphasizes the importance of carefully selecting sites for street tree planting, particularly in areas experiencing high temperatures and an extreme UHI effect. As mentioned, canopy coverage and street tree planting are not equally distributed across the city. Trees have a significant impact on the environment, particularly in their ability to reduce temperatures and mitigate the UHI effect.
Integrating indicators for extreme heat and UHI effect into the urban forest expansion master plan can support the city’s efforts to identify areas for tree planting. This ensures that the expansion of canopy coverage is strategically planned to mitigate heat risks across the city, with equitable allocation to ensure all NYC residents benefit from its effects.
This strategy aims to mitigate the adverse impacts of UHI, enhance urban resilience, and promote community well-being by strategically adding trees to areas most vulnerable to extreme heat. Additional research and data are necessary to identify the areas at the greatest risk from extreme heat and to implement the most effective nature-based solutions, such as green roofs, green walls, and tree planting.
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The canopy calculations along streets were confined to a 100-foot width, excluding open spaces and parks from the assessment.
The statistical analysis of hot spots includes results with (+/-3, +/-2, and +/-1 bins), representing 99%, 95%, and 90% confidence levels, respectively. A value of 0 indicates no statistical significance.
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Aminipouri, M.; Knudby, A. J.; Krayenhoff, E. S. et al.2019 Modeling the impact of increased street tree cover on mean radiant temperature across Vancouver’s local climate zones. Urban Forestry & Urban Greening 39: 9–17.
Google Environmental Insights Explorer. (2023, August). New York—Tree canopy. Google EIE.
NYC DPR. (2017, October 4). 2015 Street Tree Census—Tree Data
NYC OTI. (2022, September 23). Tree Canopy Change (2010—2017)
NYSERDA. (2023, October 10). Final Disadvantaged Communities (DAC) 2023.
The Trust for Public Land. (2019, September 13). Urban Heat Island Severity for U.S. Cities 2019.