The sign on the left (on the bank of the Murrumbidgee River at Hay, NSW) is a warning that river red gums, such as the tree the sign is nailed onto, routinely drop
large branches without warning. Large and heavy falling branches can damage tents, vehicles and caravans and cause injury to anybody hit by the falling branch.
An unusual feature of these falling branches is that the event often takes place on calm, hot days when visitors least expect branches to fall because there
is no wind. The silence of a hot, still afternoon is broken by the resounding crack of a branch breaking followed by the thump of impact with the ground.
The picture at left shows a branch fallen from a river red gum at Darlington Point on the Murrumbidgee River in New South Wales. The potential for damage to be
caused by such a large branch is clear. The next picture is of the stump left in the tree. The branch is about 30 centimetres in diameter at the point of break.
One reason given for branches falling from river red gums is that sap in the horizontal branches dries out in the heat and loses its strength.
In the fallen branch at Darlington Point, lack of strength at the point of the break is relevant. The bottom picture shows rotten and weak timber inside
the branch where it broke. The intact exterior bark appears to be covering sound timber but the large branch is seriously weakened and any further
loss of strength could cause a break.
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