Species clustering, climate effects, and introduced species in 5 million city trees across 63 US cities

  1. Dakota E McCoy
  2. Benjamin Goulet-Scott  Is a corresponding author
  3. Weilin Meng
  4. Bulent Furkan Atahan
  5. Hana Kiros
  6. Misako Nishino
  7. John Kartesz
  1. Stanford University, United States
  2. Harvard University, United States
  3. Independent Researcher, United States
  4. Worcester Polytechnic Institute, United States
  5. The Biota of North America Program (BONAP), United States

Abstract

Sustainable cities depend on urban forests. City trees-pillars of urban forests - improve our health, clean the air, store CO2, and cool local temperatures. Comparatively less is known about city tree communities as ecosystems, particularly regarding spatial composition, species diversity, tree health, and the abundance of introduced species. Here, we assembled and standardized a new dataset of N=5,660,237 trees from 63 of the largest US cities with detailed information on location, health, species, and whether a species is introduced or naturally occurring (i.e., 'native'). We further designed new tools to analyze spatial clustering and the abundance of introduced species. We show that trees significantly cluster by species in 98% of cities, potentially increasing pest vulnerability (even in species-diverse cities). Further, introduced species significantly homogenize tree communities across cities, while naturally occurring trees (i.e., 'native' trees) comprise 0.51%-87.3% (median=45.6%) of city tree populations. Introduced species are more common in drier cities, and climate also shapes tree species diversity across urban forests. Parks have greater tree species diversity than urban settings. Compared to past work which focused on canopy cover and species richness, we show the importance of analyzing spatial composition and introduced species in urban ecosystems (and we develop new tools and datasets to do so). Future work could analyze city trees and socio-demographic variables or bird, insect, and plant diversity (e.g., from citizen-science initiatives). With these tools, we may evaluate existing city trees in new, nuanced ways and design future plantings to maximize resistance to pests and climate change. We depend on city trees.

Data availability

All data and code are available in the main text or the supplementary materials. The datasheets of city tree information from 63 cities Figure 1-source data 1 (63 .csv files) have been uploaded to Dryad: https://doi.org/10.5061/dryad.2jm63xsrf.

The following data sets were generated

Article and author information

Author details

  1. Dakota E McCoy

    Department of Materials Science and Engineering, Stanford University, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8383-8084
  2. Benjamin Goulet-Scott

    Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, United States
    For correspondence
    bgoulet@g.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2004-6586
  3. Weilin Meng

    Independent Researcher, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Bulent Furkan Atahan

    Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Hana Kiros

    Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Misako Nishino

    The Biota of North America Program (BONAP), Chapel Hill, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. John Kartesz

    The Biota of North America Program (BONAP), Chapel Hill, United States
    Competing interests
    The authors declare that no competing interests exist.

Funding

National Science Foundation (Postdoctoral Research Fellowships in Biology,2109465)

  • Dakota E McCoy

National Science Foundation (Research Experience for Undergraduates (REU),1757780)

  • Bulent Furkan Atahan

Stanford University (Science Fellowship)

  • Dakota E McCoy

The Franklin Delano Roosevelt Foundation (Summer Research Grant)

  • Hana Kiros

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Yuxin Chen, Xiamen University, China

Version history

  1. Received: February 14, 2022
  2. Preprint posted: March 20, 2022 (view preprint)
  3. Accepted: September 11, 2022
  4. Accepted Manuscript published: September 27, 2022 (version 1)
  5. Version of Record published: October 18, 2022 (version 2)

Copyright

© 2022, McCoy et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Dakota E McCoy
  2. Benjamin Goulet-Scott
  3. Weilin Meng
  4. Bulent Furkan Atahan
  5. Hana Kiros
  6. Misako Nishino
  7. John Kartesz
(2022)
Species clustering, climate effects, and introduced species in 5 million city trees across 63 US cities
eLife 11:e77891.
https://doi.org/10.7554/eLife.77891

Share this article

https://doi.org/10.7554/eLife.77891

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