Hey @PaulF, you didn't get a closer shot of the leaves by any chance? Showing the glands (nodes) between the branchlets is a good way of telling whether its a Silver Wattle or Black Wattle. With Silver Wattle there is one gland at the junction of the branchlets, whereas with Black Wattle they are more randomly placed. Hope this helps, check this out for an idea of what I'm talking about :) https://keys.lucidcentral.org/keys/v3/eafrinet/weeds/key/weeds/Media/Html/Acacia_mearnsii_(Black_Wattle).htm
I will get a better photo on my next walk to clarify the identification. There are the dominant species on the lower section of the Tower Lane track. Thanks for the assist on what to look for.