Sheoak

Photo:

Sheoak

Go Back

What does Sheoak look like?

The Sheoak doesn’t have big leaves, instead they have branchlets with different segments that resemble pine needles. They do have miniature leaves that you can see when you snap a branchlet on one of its joins.

Another characteristic feature are the spiny “cones”, about the size of an acorn but with a texture more resembling a pine cone. However, sheoak “cones” are actually a woody fruit. Male specimens bear no fruit and are sometimes colloquially referred to as a “heoak”.

Where is Sheoak found?

There are about 50 species of Allocasuarina and Casuarina that are known as Sheoaks in Australia. They are found across Australia and are well adapted to survive throughout inland regions and on the coast.

Fast facts:

  1. Allocasurinas are known as evergreens – they are green all year round. 
  2. The term “casuarina” was used because their needle-like leaves look very similar to a cassowary feather.

Sheoaks – the full story

There are about 50 species of Allocasuarina and Casuarina that are known as Sheoaks in Australia. The term “casuarina” was used because their branchlets look very similar to a cassowary feather. They are found across Australia and are well adapted to survive throughout inland regions and on the coast.

Sheoaks are very unusual plants because they have separate male and female plants. Each year the males will turn a dusky red colour as they release their pollen. The female trees have small red flowers and lots of seed cones.

Sheoak trees are notable for their long, segmented branchlets that function as leaves. Formally termed cladodes, these branchlets can look like pine needles, although sheoaks are actually flowering plants . 

Another characteristic feature are the spiny “cones”, about the size of an acorn but with a texture also like a pine cone. However, the “cones” are actually a woody fruit. Male specimens bear no fruit and are sometimes jokingly referred to as a “heoak”.

Sheoaks are like the popular kids in wildlife school. Everyone wants to hang out with the sheoak. From the pollen on the tips of the branches, right down to the nodules on the roots, there is food and shelter for a wide-range of buddies.

The Glossy Black Cockatoo will only eat the seeds from a sheoak. Land clearing has meant these birds are now nationally endangered. Planting sheoaks in your garden could help feed these rare buddies.

The long needle-like leaves attract plenty of insects for the insectivorous buddies like fantail birds to eat. Small mammals like bandicoots enjoy digging up the little nodules from the roots.

It was once thought that their leaves can poison the soil as things rarely grow under a sheoak. This is untrue and they are actually a great help in the garden. The fallen leaves create a mulch that can fertilise the soil for your garden plants and  keep down weed growth. Their size can also mean they are great as a windbreak and can also help prevent and improve soil erosion.

You can plant these super sheoaks anytime of year and watch them quickly grow into trees up to 30 metres. You can also grow smaller sheoaks that cover the ground and offer shelter to lizards.

They are frost and drought tolerant and can live in just about any climatic condition you can throw at them.

Sheoaks love:

  • Bees who help distribute the male tree’s pollen
  • Bacteria in their roots which convert nitrogen in the air into nitrate in the soil, aka plant food.
  • Any weather rain, hail or shine. They are very hardy

But they don’t like:

  • Being called messy – their dropping needle-like leaves actually make great mulch.
  • Being misunderstood because they grow quickly and drop lots of leaves and seeds. These can be positives too and make them a favourite for many other buddies in your backyard!
Print this page