Bark tells you most of it
For the eucalypts on the North Shore, the lower trunk is where identification happens. Here is what you are likely to have.
Blackbutt. Rough, dark, fissured bark on the lower two to five metres, then smooth white or cream bark above with a clean transition. Tall and straight. Extremely common on the shale ridge through Gordon, Pymble and St Ives, where it reaches forty metres and more.
Sydney blue gum. Smooth blue-grey to white trunk shedding in long ribbons, sometimes with a short rough stocking at the base. Tall, straight and often growing in groups. A defining species of Blue Gum High Forest.
Turpentine. Persistent, deeply furrowed reddish-brown bark all the way up the trunk — no smooth section at all. Leaves have a noticeably pale, felted underside. A defining species of Sydney Turpentine-Ironbark Forest.
Angophora. Smooth pink to orange bark, often heavily contorted, gnarled limbs spreading near-horizontally. Grows out of sandstone and rock outcrops through Hornsby, Lane Cove and Castlecrag. Not technically a eucalypt, though it looks like one.
Sydney peppermint. Finely fibrous grey bark, narrow leaves smelling strongly of peppermint when crushed. Very common on the sandstone slopes.
Scribbly gum. Smooth white bark marked with the distinctive wandering insect scribbles. Sandstone country.
The planted material
Almost every older North Shore garden also holds exotics planted between the 1920s and the 1970s.
Camphor laurel. Dense, dark, glossy foliage, aromatic when crushed, spreading habit. A declared weed across New South Wales, shallow-rooted, and responsible for a large share of lifted driveways and damaged footings. Usually the most straightforward removal on a block.
Liquidambar. Star-shaped leaves, spiky fruit balls, brilliant autumn colour, aggressive surface roots. Planted everywhere in the fifties, far too close to houses.
Cocos palm. Feather-fronded palm dropping enormous quantities of orange fruit. Weed-listed in much of Sydney and a persistent nuisance in pools and gutters. See palm removal.
Privet. Small tree with glossy leaves and heavily scented cream flowers, a major bushland weed and a well-known allergen. Suckers persistently from the roots.
Why it matters before you ring anyone
Species determines the permit position, the pruning response, the cutting method and the price. A camphor laurel and a turpentine of identical size are completely different jobs.
If you are not sure what you have, take a photo of the bark at chest height and another of the leaves, and ring (02) 9090 4915. The endangered forest article covers the protected natives, the permits article covers consent, and the blog has the rest.
Frequently asked questions
Why does the species change what I am allowed to do?
Because council exemption lists are species-based. Declared weed species such as camphor laurel and privet are frequently exempt from permit requirements, while natives forming part of a listed endangered community attract the strongest protection available. The same size tree can be freely removable or effectively untouchable depending on what it is.
Can you identify a tree from a photograph?
Often, yes, if the photo shows the bark on the lower trunk clearly and there is a second shot of the leaves and any fruit. Bark is the most useful single feature for the local eucalypts. Where it is genuinely ambiguous — and some of the gums are — somebody needs to stand under it.