Logical Tree Management has been heavily involved in emergency works and the subsequent clean-up process, removing trees that have suffered complete failure from ground level, as well as the dismantling and removal of hazardous trees damaged beyond repair. In some cases failed trees have been healthy and structurally sound specimens that prior to failure, would not have displayed any obvious indicators that failure was likely to occur. In other cases, the failure has occurred at an obvious structural weak point which, had the tree been assessed by an arborist, could have been addressed prior to the tree failing.
This image is of a failed primary limb union in a Red Iron bark (Eucalyptus sideroxylon). During a high wind event the limb failed, landing on and partially crushing a parked car. What’s noticeable is the presence of a fungus inside the union obvious by the mantle of fungal mycelium growing over recently torn heartwood. The presence of the recently formed mycelium indicates the limb union had partially fractured prior to the limb failing completely. From the picture we can see that when the union finally failed, only a thin strip of wood around the edge of the union had been holding the limb.
Although this prior, partial failure of the union is mostly hidden, the union was inherently structurally compromised, which to the observing eye of an arborist is immediately evident by the acute angle of attachment of the union and the accompanying flaring of the stem on either side of the union. If the tree had been assessed by an arborist the inherent defect would have been noted and a risk mitigating processes could have been enacted. The tree could have had a support mechanism installed, or the stem could have been removed entirely.
Whether undertaking a ground based or aerial (climbing) inspection, assessing tree structure and the related risk is a core element of arboricultural assessments. After an extreme weather event, even if there are no obvious signs of damage to other trees on your property, it is sound management to have your property inspected by an arborist who may detect signs of damage in your trees that could be problematic later.
Rhys Oldmeadow – Operations Manager