Melaleuca

Melaleuca quinquenervia
Family: Myrtaceae

Natural Historymelaleuca
Multiple trunks of melaleuca
Photo credit: Larry Korhnak, University of Florida

Melaleuca is an invasive exotic plant that is originally from Australia. It is sometimes called punk tree, white bottle-brush tree or paper-bark tree. This member of the Eucalyptus family has a characteristic camphor-like scent when the leaves are crushed. The flowers produce chemical compounds that cause respiratory problems for some people. Others think the blossoms, which resemble bottle-brushes, have a scent similar to mashed potatoes and gravy.

The trees spread rapidly by producing and storing many seeds. In fact, one tree is capable of producing as many as one million seeds per year. When the trees are stressed, such as by fire or frost, they release even more seeds. In some locations, Melaleuca can out-compete and replace as much as 50 acres of native vegetation per day. The seeds are dispersed by both wind and water and quickly establish new stands.

Habitat & Range

Melaleuca is native to the South Pacific but can now be found growing rampant in many wetlands in South Florida and Louisiana. The trees are especially dense and troublesome in the Everglades. The trees are very adaptable and can live in either dry or wet settings. They are common in South Florida swamps and marshes and can  form dense monocultures that pose a serious threat to natural communities.

Wildlife Use

While the trees can cause serious environmental problems, they are valuable to honeybees, bats and certain birds that  are attracted to melaleuca blossoms for their nectar.

Human Use

Melaleuca was introduced to the United States in the early 1900's as an ornamental tree and also to help dry up swampy areas.  Control of melaleuca is a serious problem in Florida. Although the trees are highly flammable, they reproduce quickly after fires. Some experiments involve the introduction of Australian snout beetles, who are natural enemies and feed only on melaleuca leaves.  Trees removed for control are sometimes sold as mulch, which has been treated with high heat to prevent remnant seeds from germinating.


 

Identifying Characteristics

Size/Form: Melaleuca is a sub-tropical evergreen tree that may grow up to 50' to 80' tall. It grows in dense thickets and has spongy, peeling, paper-thin bark.
Leaves: The leaves are simple, alternately-arranged and oval to elliptical in shape. The 1" - 2" leaves are greyish-green and have distinctly parallel veins. The leaves have a camphor-like odor when they are crushed.
Bark: The bark is spongy and grows in thin, white layers.
Flowers: The flowers are white blossoms growing on brush-like spikes in spring and summer months. They are fragrant and are often an allergen .
Fruit: Fruits are small, cylindrical or square woody capsules, containing many seeds.
Similar Trees on the Florida 4-H Forest Ecology Contest List:
  • None. This is the only tree on the list bearing flattened leaves with parallel veins.

 

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