Western Tree Failure Database/California Tree Failure Report Program

Acacia baileyana and Acacia melanoxylon 2016

Acacia

 A. baileyanaA. melanoxylon
Number of reports3184
Mean DBH16"19"
Mean age21 years32 years
Mean height26'27'
Season of failure:  
November-April90%84%
May-October10%16%
Trunk failures38%39%
Branch failures13%17%
Root failures49%44%
Sites:  
Residential or street55%51%
Park3%30%
Parking lot16%7%
Other26%12%
Medium/high site use74%74%
Structural defects:  
no decay43%44%
some decay57%56%
dense crown61%33%
failed portion dead48%5%
codominance19%20%
Mean branch diameter10"12"
Failure at attachment4 of 5 cases15 of 18 cases
Mean ht. of trunk failure2'6'
Mean diam. of trunk failure21"16"
Trunk fail at ground level5 of 10 cases19 of 37 cases
Wind:  
<5mph3%10%
5-25mph29%23%
>25mph68%67%
Precipitaion:  
none25%34%
some75%66%