A time series of urban forestry in Los Angeles

Thomas Welch Gillespie, Stephanie Pincetl, Shea Brossard, Jenny Smith, Sassan Saatchi, Diane Pataki, Jean Daniel Saphores

Research output: Contribution to journalArticle

  • 19 Citations

Abstract

There has been an increasing interest in the evolution of urban forests. This research uses historic and digital aerial photography to quantify changes in tree density in Los Angeles, California since the 1920's. High-resolution geographic information system analysis (4 to 6 time periods) of three regions (San Fernando Valley, Hollywood, Los Angeles Basin) of Los Angeles reveals that there has not always been an increase in tree density with time. Tree densities on public and private land were highest in the 1940's in Hollywood, while the San Fernando Valley and Los Angeles Basin experienced a near linear increase in tree density on both private and public land since the 1920's. When historic tree density reconstructions were examined for the 15 Los Angeles city council districts from the 1920's, 1950's and 2006, most districts in Los Angeles have experienced a significant increase in tree density, however, there has been wide variation in tree densities among city council districts. Trees densities have generally been higher on private land since the 1920's and currently tree densities on private land are significantly higher than on public land. Results suggest the evolution of urban forests in Los Angeles mirrors the dynamics of urban forests in desert and grassland cities. It is possible to reconstruct the development of urban forests in sections of cities using historic and contemporary aerial photography. We estimated that Los Angeles averages approximately 104 trees per hectare (82 private land, 22 public land) based on 2006 imagery at 0.3 m resolution, however, field validation suggests that we identified only 73% of trees. Although there is still space to plant trees on public land, private land owners will need to be heavily involved in order to achieve the goals of Los Angeles' Million Tree Initiative.

LanguageEnglish
Pages233-246
Number of pages14
JournalUrban Ecosystems
Volume15
Issue number1
DOIs
StatePublished - Mar 2012
Externally publishedYes

Fingerprint

urban forestry
forestry
time series
private land
municipal council
district
photography
aerial photography
systems analysis
desert
valley
information system
reconstruction
basin

Keywords

  • Aerial photography
  • Geographic information system
  • Los Angeles
  • Public and private land
  • Time series
  • Tree density
  • Urban forests

ASJC Scopus subject areas

  • Urban Studies
  • Ecology

Cite this

Gillespie, T. W., Pincetl, S., Brossard, S., Smith, J., Saatchi, S., Pataki, D., & Saphores, J. D. (2012). A time series of urban forestry in Los Angeles. Urban Ecosystems, 15(1), 233-246. https://doi.org/10.1007/s11252-011-0183-6

A time series of urban forestry in Los Angeles. / Gillespie, Thomas Welch; Pincetl, Stephanie; Brossard, Shea; Smith, Jenny; Saatchi, Sassan; Pataki, Diane; Saphores, Jean Daniel.

In: Urban Ecosystems, Vol. 15, No. 1, 03.2012, p. 233-246.

Research output: Contribution to journalArticle

Gillespie, TW, Pincetl, S, Brossard, S, Smith, J, Saatchi, S, Pataki, D & Saphores, JD 2012, 'A time series of urban forestry in Los Angeles' Urban Ecosystems, vol. 15, no. 1, pp. 233-246. https://doi.org/10.1007/s11252-011-0183-6
Gillespie TW, Pincetl S, Brossard S, Smith J, Saatchi S, Pataki D et al. A time series of urban forestry in Los Angeles. Urban Ecosystems. 2012 Mar;15(1):233-246. https://doi.org/10.1007/s11252-011-0183-6
Gillespie, Thomas Welch ; Pincetl, Stephanie ; Brossard, Shea ; Smith, Jenny ; Saatchi, Sassan ; Pataki, Diane ; Saphores, Jean Daniel. / A time series of urban forestry in Los Angeles. In: Urban Ecosystems. 2012 ; Vol. 15, No. 1. pp. 233-246.
@article{2b91b34e444f4e809e1c53d627a8433b,
title = "A time series of urban forestry in Los Angeles",
abstract = "There has been an increasing interest in the evolution of urban forests. This research uses historic and digital aerial photography to quantify changes in tree density in Los Angeles, California since the 1920's. High-resolution geographic information system analysis (4 to 6 time periods) of three regions (San Fernando Valley, Hollywood, Los Angeles Basin) of Los Angeles reveals that there has not always been an increase in tree density with time. Tree densities on public and private land were highest in the 1940's in Hollywood, while the San Fernando Valley and Los Angeles Basin experienced a near linear increase in tree density on both private and public land since the 1920's. When historic tree density reconstructions were examined for the 15 Los Angeles city council districts from the 1920's, 1950's and 2006, most districts in Los Angeles have experienced a significant increase in tree density, however, there has been wide variation in tree densities among city council districts. Trees densities have generally been higher on private land since the 1920's and currently tree densities on private land are significantly higher than on public land. Results suggest the evolution of urban forests in Los Angeles mirrors the dynamics of urban forests in desert and grassland cities. It is possible to reconstruct the development of urban forests in sections of cities using historic and contemporary aerial photography. We estimated that Los Angeles averages approximately 104 trees per hectare (82 private land, 22 public land) based on 2006 imagery at 0.3 m resolution, however, field validation suggests that we identified only 73{\%} of trees. Although there is still space to plant trees on public land, private land owners will need to be heavily involved in order to achieve the goals of Los Angeles' Million Tree Initiative.",
keywords = "Aerial photography, Geographic information system, Los Angeles, Public and private land, Time series, Tree density, Urban forests",
author = "Gillespie, {Thomas Welch} and Stephanie Pincetl and Shea Brossard and Jenny Smith and Sassan Saatchi and Diane Pataki and Saphores, {Jean Daniel}",
year = "2012",
month = "3",
doi = "10.1007/s11252-011-0183-6",
language = "English",
volume = "15",
pages = "233--246",
journal = "Urban Ecosystems",
issn = "1083-8155",
publisher = "Kluwer Academic Publishers",
number = "1",

}

TY - JOUR

T1 - A time series of urban forestry in Los Angeles

AU - Gillespie, Thomas Welch

AU - Pincetl, Stephanie

AU - Brossard, Shea

AU - Smith, Jenny

AU - Saatchi, Sassan

AU - Pataki, Diane

AU - Saphores, Jean Daniel

PY - 2012/3

Y1 - 2012/3

N2 - There has been an increasing interest in the evolution of urban forests. This research uses historic and digital aerial photography to quantify changes in tree density in Los Angeles, California since the 1920's. High-resolution geographic information system analysis (4 to 6 time periods) of three regions (San Fernando Valley, Hollywood, Los Angeles Basin) of Los Angeles reveals that there has not always been an increase in tree density with time. Tree densities on public and private land were highest in the 1940's in Hollywood, while the San Fernando Valley and Los Angeles Basin experienced a near linear increase in tree density on both private and public land since the 1920's. When historic tree density reconstructions were examined for the 15 Los Angeles city council districts from the 1920's, 1950's and 2006, most districts in Los Angeles have experienced a significant increase in tree density, however, there has been wide variation in tree densities among city council districts. Trees densities have generally been higher on private land since the 1920's and currently tree densities on private land are significantly higher than on public land. Results suggest the evolution of urban forests in Los Angeles mirrors the dynamics of urban forests in desert and grassland cities. It is possible to reconstruct the development of urban forests in sections of cities using historic and contemporary aerial photography. We estimated that Los Angeles averages approximately 104 trees per hectare (82 private land, 22 public land) based on 2006 imagery at 0.3 m resolution, however, field validation suggests that we identified only 73% of trees. Although there is still space to plant trees on public land, private land owners will need to be heavily involved in order to achieve the goals of Los Angeles' Million Tree Initiative.

AB - There has been an increasing interest in the evolution of urban forests. This research uses historic and digital aerial photography to quantify changes in tree density in Los Angeles, California since the 1920's. High-resolution geographic information system analysis (4 to 6 time periods) of three regions (San Fernando Valley, Hollywood, Los Angeles Basin) of Los Angeles reveals that there has not always been an increase in tree density with time. Tree densities on public and private land were highest in the 1940's in Hollywood, while the San Fernando Valley and Los Angeles Basin experienced a near linear increase in tree density on both private and public land since the 1920's. When historic tree density reconstructions were examined for the 15 Los Angeles city council districts from the 1920's, 1950's and 2006, most districts in Los Angeles have experienced a significant increase in tree density, however, there has been wide variation in tree densities among city council districts. Trees densities have generally been higher on private land since the 1920's and currently tree densities on private land are significantly higher than on public land. Results suggest the evolution of urban forests in Los Angeles mirrors the dynamics of urban forests in desert and grassland cities. It is possible to reconstruct the development of urban forests in sections of cities using historic and contemporary aerial photography. We estimated that Los Angeles averages approximately 104 trees per hectare (82 private land, 22 public land) based on 2006 imagery at 0.3 m resolution, however, field validation suggests that we identified only 73% of trees. Although there is still space to plant trees on public land, private land owners will need to be heavily involved in order to achieve the goals of Los Angeles' Million Tree Initiative.

KW - Aerial photography

KW - Geographic information system

KW - Los Angeles

KW - Public and private land

KW - Time series

KW - Tree density

KW - Urban forests

UR - http://www.scopus.com/inward/record.url?scp=84857659474&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84857659474&partnerID=8YFLogxK

U2 - 10.1007/s11252-011-0183-6

DO - 10.1007/s11252-011-0183-6

M3 - Article

VL - 15

SP - 233

EP - 246

JO - Urban Ecosystems

T2 - Urban Ecosystems

JF - Urban Ecosystems

SN - 1083-8155

IS - 1

ER -