Casuarina cunninghamiana is the standard tree for holding a riverbank together. Deep binding roots stabilise eroding soil while fine weeping needle-like foliage filters wind rather than blocking it, which reduces the turbulence a solid windbreak creates on the sheltered side.
The River She Oak grows very fast at 1 to 2 metres per year, reaching 15 to 30 metres tall and 10 to 15 metres wide with a tall straight trunk and soft drooping canopy. It is a mainstay of rural shelterbelts, revegetation programs, erosion control and large-scale civic screening.
This Australian native is frost hardy, surviving heavy and frequent frost without damage, and tolerates poor soils, waterlogging, drought and moderate salinity. Like all casuarinas it fixes nitrogen, which improves degraded ground as it grows.
Frequently Asked Questions
About Casuarina cunninghamiana
How big does Casuarina cunninghamiana grow?
The River She Oak reaches 15 to 30 metres tall and 10 to 15 metres wide. It is a large tree for rural properties, riverbanks and parkland rather than suburban gardens.
How fast does River She Oak grow?
Very fast, at 1 to 2 metres per year. It is one of the quickest options for establishing shelter, screening or bank stabilisation.
Why is it used for riverbank stabilisation?
Its deep binding root system holds soil against flowing water, and it tolerates periodic inundation. It is the standard species for erosion control along Australian watercourses.
Does it make a good windbreak?
Yes. The fine needle-like foliage filters wind rather than blocking it, which reduces the turbulence and eddying that occurs behind a solid barrier.
Is Casuarina cunninghamiana frost hardy?
Yes. It is frost hardy and survives heavy and frequent frost without damage, and also tolerates drought, waterlogging and moderate salinity.
Does anything grow underneath it?
The fallen needles form a dense mat that suppresses most understorey growth. This suits low-maintenance shelterbelts but is worth planning around in a garden.
How far apart should I plant it for a windbreak?
Plant 3 to 4 metres apart for a shelterbelt row, or 8 to 10 metres apart where each tree should develop a full canopy.