When beauty becomes an invader
The recurring trap: a tough, fast, pretty tree planted for shade or shelter, that escapes and smothers a continent.
- 01
Trees№ 4974 minTree of Heaven: The Invader That Grows in Brooklyn
A fast, tough, foul-smelling Asian tree that poisons its neighbours, resprouts from any cut, and now hosts the pest threatening whole crops.
- 02
Trees№ 0684 minCasuarina: The She-Oak That Is Neither Pine Nor Oak
An Australian tree that mimics a conifer, fixes nitrogen without being a legume, whistles in the wind, holds the coast together — and smothers beaches where it does not belong.
- 03
Trees№ 2884 minMelaleuca and Tea Tree: Paperbark, Healing Oil, and a Swamp-Draining Invader
Australian myrtles with peeling paper bark and antiseptic oil — the source of tea tree oil, tough survivors of fire and flood, and the tree that tried to drink the Everglades dry.
- 04
Trees№ 4834 minTamarisk: The Feathery Tree That Salts the Ground and Drinks the River
A wispy pink-flowered desert tree that survives on salt water, pumps salt onto the soil to poison its rivals, and became the great water-guzzling invader of the American West.
- 05
Trees№ 0824 minChinaberry: The Bead Tree That Feeds Insects to Nothing
A fast, pretty, lilac-flowered relative of neem — carrying the same natural insecticide, strung into rosary beads for centuries, poisonous to people, and now a widespread invader of warm countrysides.
- 06
Trees№ 3484 minPepper Tree: Pink Peppercorns and a Pretty Invader
Graceful, weeping South American trees whose rose-coloured berries are sold as 'pink peppercorns' — kin to the cashew, beloved as ornamental shade, and now among the worst invaders of warm coasts and wetlands.
- 07
Trees№ 1503 minElaeagnus: The Silver-Leaved Nitrogen Fixers That Went Rogue
Tough silvery shrubs that fix their own nitrogen without being legumes, bear tart edible berries, and were planted everywhere for wildlife and reclamation — before autumn olive and Russian olive became runaway invaders.
- 08
Trees№ 1584 minFalcataria: One of the Fastest-Growing Trees on Earth
A nitrogen-fixing tropical legume that can grow seven metres in a year — a prized fast plantation timber and shade tree that has also become a towering, brittle invader of Pacific islands.
- 09
Trees№ 1924 minGorse and Broom: Nitrogen Fixers That Burn and Invade
Spiny, yellow-flowered legume shrubs that colonise the poorest ground, fix nitrogen, fire their seeds explosively — and become fierce invaders abroad.