Ongoing research

Western Tree Failure Database/California Tree Failure Report Program: Page

50 or more

There are 50 or more reports for the following species as of January 10, 2024. Report numbers for species do not provide an assessment of the frequency of failure for the species (i.e., how often a species fails relative to its occurrence in a population of trees).
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Western Tree Failure Database/California Tree Failure Report Program: Page

Big Wind in Marin County

Big wind in Marin Thursday morning, March 24, 2011, in west Marin it was raining and windy. It felt like a tornado, but according to the Marin Independant Journal, the meteorologists say "No. It was a 50-60 mph wind gust.
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Western Tree Failure Database/California Tree Failure Report Program: Page

Umbellularia californica

California bay root failure Photo: R. Edberg California bay root failure Photo: R. Edberg California bay trunk failure Photo: R. Edberg California bay branch failure Photo: R. Bushwag California bay branch failure Photo: R.
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Western Tree Failure Database/California Tree Failure Report Program: Page

Ulmus parvifolia

Evergreen elm branch failure Photo:M. Camfield Evergreen elm branch failure Photo: B.
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Western Tree Failure Database/California Tree Failure Report Program: Page

Calocedrus decurrens

Incense cedar root failure Photo: K. Jones Incense cedar trunk failure Photo: R.
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Western Tree Failure Database/California Tree Failure Report Program: Page

Pinus attenuata

knobcone pine root failure Photo: S.
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Western Tree Failure Database/California Tree Failure Report Program: Page

Ficus fracture

ficus fracture Why did it fail? Multiple trunks? Codominance? Branch end weight? All of the above?
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Western Tree Failure Database/California Tree Failure Report Program: Page

Quercus agrifolia summary comparisons

Coast live oak is the most commonly reported species in the CTFRP database. (See CTFRP Statistics/50 or more) It is the most widely planted native California oak in urban landscapes. Many remnant coast live oaks of great age can be found within developed areas.
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Western Tree Failure Database/California Tree Failure Report Program: Page

Edberg and Berry 1999

Patterns of Structural Failures in Urban Trees: Coast Live oak (Quercus agrifolia)...
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Western Tree Failure Database/California Tree Failure Report Program: Page

Branch failures by month

The database (September, 2011) contains 1878 reports of branch failures for which a date is recorded. Eight genera have 87 or more branch failure reports. The following table lists the percentage of failures that occurred for each genus for the periods May-October and November-April.
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