Resilient Trees

Does a Coast Live Oak in Santa Monica do as well as one in Palm Desert? How much more water does a Jacaranda growing in Riverside use versus one that lives in Downtown Los Angeles? Is a tree that’s planted in a concrete median using the same amount of water as one that’s in the middle of a park? These are some of the types of questions the researchers will be seeking to answer.


Over 100 community scientists collected data from nearly 800 trees 2015-2016, recording GPS coordinates, tree health, trunk and canopy size, and the percent permeable surface around each tree. This data provides a large enough sample size of trees to make meaningful conclusions and researchers at UC Riverside can now conduct additional analyses to determine each species’ physiological performance across different climate zones.


Resilient Trees 1.0 studied ten different tree species:
California Natives-
  • California Sycamore (Platanus racemosa)
  • Coast Live Oak (Quercus agrifolia)
  • Pink Dawn Chitalpa (Chitalpa taskentensis)
Classically planted species (ones that were frequently planted in the past and are still with us today)-
  • Southern Magnolia (Magnolia grandiflora)
  • Jacaranda (Jacaranda mimosifolia)
  • Shamel Ash (Fraxinus uhdei)
Modern species (ones that are commonly planted in the present day and will be with us for years to come)-
  • Crepe Myrtle (Lagerstroemia indica)
  • Tipu (Tipuana tipu)
  • African Fern Pine (Podocarpus gracillior or Afrocarpus falcatus)
  • Brisbane Box (Lophostemon confertus)
Resilient Trees 2.0 studied another ten tree species:
  • African Sumac (Rhus lancea)
  • Olive Tree (Olea europea)
  • Strawberry Tree (Arbutus unedo)
  • Indian Rosewood (Dalbergia sissoo)
  • Chinese Pistache (Pistacia chinensis)
  • Chinese Flame Tree (Koelreuteria bipinnata)
  • Netleaf Hackberry (Celtis reticulata)
  • Engelmann Oak (Quercus engelmannii)
  • Water Gum (Tristaniopsis laurina)
  • Pink Trumpet Tree (Handroanthus impetiginosus)

Thanks to the efforts of these community scientists, the lab now has enough usable trees to proceed with its research into what the right trees are for each place- a valuable task that would otherwise be delayed by months or years without help.

Interested in the raw data?  Visit the Resilient Trees 1.0 iNaturalist project page or download the Excel file here: Resilient Trees 1.0 Data (All).  For Resilient Trees 2.0, visit the iNaturalist project page or download the Excel file here: Resilient Trees 2.0 Data (All)

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