The Invasive Australian Pine Tree & How to Get Rid of It

Jun 25, 2020 . 2 min read

The Australian pine is an invasive tree found primarily in FL, HI, CA, AZ, and TX. In 1898, the USDA first planted Australian pine to stabilize banks and use as lumber. Today, this invasive species interferes with the plants, wildlife, and soil around it.

How To Identify the Australian Pine

Despite its name, the Australian pine has no relation to pine trees. While it has cone-shaped fruit and leaves that look like pine needles, it belongs to the Casuarina genus instead of the Pinus genus. The distinct traits of an Australian pine include:

Leaves: The "leaves" that you see on an Australian pine are actually tiny, multi-jointed branchlets with even smaller leaves. Each of these branchlets measures about 4 to 8 inches long and has a grayish-green color.
Height: Depending on the species of Australian pine and its growing conditions, it can grow as high as 150 feet tall.
Bark: An Australian pine tree's bark ranges from reddish-brown to gray in color and has a rough, peeling texture.
Fruit: Inside the cone-like clusters on an Australian pine, you'll find tiny, winged, and one-seeded fruit.

Destruction Caused by Australian Pine

Australian pine trees aggressively reproduce and grow throughout barrier beaches, woods, and roadsides. They cause the following threats to the local ecosystem, which is why many landowners look to remove them completely.

Native Plant Destruction and Displacement

Australian pines kill or displace native vegetation by:

Creating dense shade and litter: Australian pines cut off other plants' access to the nutrients they need. The dense thickets on these trees block rain and sunlight, causing changes in the surrounding environment's light level, soil chemistry, temperature, and available water. They also cover the ground with thick litter that blocks plant growth.
Dropping leaves containing allelopathic properties: The leaves on an Australian pine have allelopathic properties, meaning they suppress the growth of other plant life. When the leaves become litter, they directly prevent plant growth in the soil.

Beach and Soil Erosion

While the USDA thought Australian pines would prevent soil and beach erosion, this invasive tree can encourage it.

Australian pine has shallow roots that can't stabilize the ground as effectively as deep-rooted plants, and its plant-displacing properties discourage deep-rooted vegetation from growing and preventing erosion.

Wildlife Displacement

In addition to displacing plants and letting soil erode, the Australian pine displaces wildlife through the following effects:

Lack of wildlife habitat: An Australian pine does not provide a habitat for any wildlife.
Shallow root system: The shallow root system of an Australian pine destroys breeding sites for some endangered species. Baby turtles and other creatures can get tangled in these root systems, which puts their species at further risk.
Displaced habitat plants: In some cases, Australian pine trees replace the natural habitat of an animal. Since the Australian pine doesn't offer any habitat itself, the animals must find other areas to inhabit.

How To Get Rid of Australian Pines

Damaging or cutting an Australian pine stimulates its growth, so these invasive trees need a specialized removal solution. Common strategies for removing Australian pine include:

Herbicides: Australian pine responds to frill/girdle, basal bark, foliar, and soil herbicide application methods. If a tree could fall and cause damage after herbicide use, we recommend cutting the tree first and using the stump application method.
Professional strategies: Trained officials may use burning or biological controls to manage large numbers of Australian pine trees. If you can't use herbicides or mechanical removal to get rid of Australian pine, consider contacting your local invasive species management organization.
Mechanical removal: If you have smaller Australian pine trees to remove from a property, you can use attachments like mulchers and stump grinders to completely eliminate the tree from your property.

Australian Pine Removal Solutions From Diamond Mowers

For continued maintenance on a property with Australian pine, we recommend using one of our mulchers to remove these trees up to 14 inches in diameter.


Skid-Steer Drum Mulcher For mulching trees up to 9 inches in diameter	Skid-Steer Forestry Disc Mulcher For cutting down trees up to 14 inches in diameter & mulching trees 6 inches in diameter