The short answer for Galston owners
Often, yes. Galston sits within the Hills Shire, where pruning or removing a protected tree usually needs council approval before any cutting starts. That is the protected tree ordinance in practice: if the tree qualifies, you apply first and cut second.
Healthy trees are covered too, along with trees under preservation orders or in conservation areas. Most councils also require a permit for any pruning beyond minor maintenance on a protected tree, including work done for a better view, because a blocked view does not exempt a tree from protection.
Why guessing is risky
Pruning or removing a protected tree without authorisation can bring severe consequences. Once a branch or tree is gone, it cannot be put back, so checking first is far easier than fixing a mistake.
Getting a clear answer before work begins
Whether a particular tree needs approval depends on its height, trunk size, species and location on your block. Some trees fall under clearing entitlements or hazard exemptions, and others stay protected.
Trees Down Under can assess the tree on your property and tell you where it stands with Hornsby Shire Council and the Hills Shire rules, so you know the position before anyone picks up a saw.