In the 20th century, the most damaging of the exotic plant species introduced into the Everglades was the Melaleuca. The scientific name is quinquenervia and is also known as the tea tree, paperback or the punk tree. Planting the Melaleuca had only one purpose, to drain the low-lying “swampy” areas for the sugar and citrus growers for new farmland.
The Melaleuca is from Australia but is also found in some of the Soloman Island and Malaysia. It is a member of the myrtle family. The Latin name is Myrtacea. In Australia, it grows in marshes and waterways. For fruit-eating bats and birds, it produces an abundance of fruits and seeds. Quite often it will be planted as a nectar source for beehives. Due to the amount of water it uses, not often will you find it in the dry Outback areas.
Starting in the 1930’s, seeds were intentionally dropped into the Everglades by air. Due to their rapid growth, they were also planted in parks and backyards for ornamentals. They were also planted along ponds and canals, acting as support props to the banks. During this time period, some were grown commercially for their wood.
Planting the Melaleuca has turned out to be a nightmare. There were no natural checks on their growth and they exploded quickly. Soon they had invaded nearly all of South Florida. The bark and the oils in the tree’s leaves make the trees extremely flammable. Ignited by the Everglades lighting-strike grass fires, they drop large numbers of seeds allowing them to beat the native plants to freshly cleared areas. Their growth rate is six feet a year. It is estimated that they cover an estimated half-million acres in South Florida.
The Melaleuca can only handle a degree of freezing temperatures. Consequently, you will rarely find them north of Tampa Bay. The concentration is the heaviest in Florida’s six frost-free areas of which include Broward, Miami-Dade, and the Keys.
Unfortunately, efforts to eradicate the trees have not been very successful. The tree will induce a massive seed fall if it is cut or damaged. Also, it is not susceptible to most herbicides.
The State has been encouraging the commercial harvesting and grinding of the Melaleuca stands for landscaping mulch and wood chips since the wood is rot, fungus and termite resistant. Introducing the Australian weevil in 1995 which attacks the tree’s seeds has not been very effective.
Photographic credit to: By Djambalawa – Own work, CC BY-SA 3.0