This is part 5 of The Garden Guide — the studio's field manual for building a native garden from bare ground in Canberra and the Southern Tablelands. Start at the overview if you've just arrived.
Identify what's there. Decide what stays. Then deal with the rest. Weeds come in three registers — this post covers the first: the woody, berrying environmental weeds that spread into bushland and compete with native habitat. These are the ones to remove, and the ones to learn by sight.
Berries are how you will actually spot them — that is what catches your eye from across a garden, and it is also how each one is spreading into the bush. Each profile below is built around the one detail that tells it apart from the plant it gets mistaken for. That's the thing worth memorising.
Privet — Ligustrum lucidum
Bright yellow-cream flower flushes, flowering everywhere in January. Waxy, glossy leaves. Purple berries in dense clusters. The tell: small white dots on the stems. Birds eat the berries and spread them into bushland.
Don't confuse it with camellias and some magnolias, which look very similar — but they have no white dots on the stem. That single detail does the whole job.
Small-leaf privet — Ligustrum sinense
Small leaves, sitting directly opposite one another on the stem. The tell is that opposite arrangement — look at the stem, not the leaf. Purple berries. Same problem as its larger cousin: straight into the bush.
Cootamundra wattle — Acacia baileyana
Australian — but not local, and a genuine problem in our bushland. Branches fold down, all on a similar axis.
Don't confuse it with Acacia dealbata (silver wattle) — which is local, and should stay. Cootamundra carries only two to four pairs of pinnae per leaf and reads distinctly grey; silver wattle carries many more. Count the pairs before you cut. Get this one wrong and you remove a native.
Pyracantha — firethorn
Giant clusters of orange-to-red berries. The tell is the thorns — you'll know. They're woody, and long enough to go through a glove. Long sleeves and thick gloves.
Celtis — Celtis australis
Pops up everywhere; not a local plant, and it's on the ACT pest plant list. The tell: a serrated edge running the entire way round the leaf, with a lopsided blade base — one side meets the stalk lower than the other. Purple berries. Seedlings come up thickly under the parent. Get them young — a seedling pulls out by hand; a tree is a job.
Cotoneaster
Many forms — groundcover through to shrubs the size of a car, planted all over Canberra. That range is exactly why it gets missed. Five-petalled flowers, red berries in clusters.
Don't confuse it with tea tree (Leptospermum), which also has five-petalled flowers and is native. Crush a leaf: a leptospermum smells. Cotoneaster won't.
Removing them
Saplings pull or dig out. Once they're tree-sized, cut and poison.
Cut and paint — the only time to use poison. Rubber gloves, a paintbrush, and glyphosate at 490g/L — the concentrate, sold as Zero and similar. Not the pre-mixed spray bottle; that is far too dilute to kill a stump. Cut the stem, then immediately paint the junction between bark and old wood — that's where the tree's veins are, and that's how the poison enters the system.
You have 15–20 seconds. Privet starts sealing the wound almost immediately and the poison stops working. Use two people: one cuts, one paints. On a big tree, drop it first, clear the limbs so you have a safe space, then re-cut the stump to reopen the wound and paint that.
The ground-level weeds — couch, ivy, and the ones you should actually leave — are covered in the next part.
This series comes from the Garden Guide I give my design clients. I write one letter a week on spatial design, craft and technology — and subscribers read the full guides first.
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