Northern Beaches Council staff have discovered 14 Swamp She Oak trees (Casuarina Glauca) illegally drilled and poisoned in Bayview Park and around the adjacent tennis courts.

The full effects of the poisoning are not known at this stage but the trees, aged between 40 and 60 years old, are already showing signs of stress with branches dying.

These trees provide important shade and visual amenity for the area and Northern Beaches Council will replace any permanently damaged trees.

Council is taking the matter very seriously and will be conducting a rigorous investigation, including installing signage and sending letters to nearby residents in an attempt to gain further information on the matter. Northern Beaches Council offers rewards for information that leads to a successful prosecution.

The tree poisoning is the latest in a recent spate of attacks that have been carried out in Manly, Collaroy and Clontarf.