Thursday, December 13, 2012

Tree Thursday - Melaleuca

Melaleuca (Punk Tree, Paper Tree)
Melaleuca quinquenervia

If Santa has a naughty tree list,  melaleuca trees would definitely be on it (at least in South Florida).  Melaleuca is an invasive, non-native tree that was brought from Australia to South Florida in the early 1900s.  Melaleuca was believed to have a high evapotranspiration rate, so it was thought that melaleuca forests would dry up the wetlands.  This sounds pretty ludicrous to us now, since we understand the importance of wetlands, but back then that would just lead to more land that could be developed! 

Since melaleuca had no natural enemies in South Florida, the tree spread like crazy (highly technical term, please let me know if you need it explained). Seeds were scattered from airplanes over the Everglades in the 1930s to facilitate the rapid establishment of melaleuca forests.  The prolific trees grow so close together that most native vegetation is squeezed out in the competition for water, sunlight, and nutrients.  A typical melaleuca tree produces thousands of seed pods, which burst open after periods of stress such as fire, flood, or almost any other disturbance.  A melaleuca tree can produce up to 20 million seeds annually. The species had invaded nearly a half-million acres in South Florida by 1994, including significant acreage within the Everglades.  Since the 1980s, there has been a concerted effort to slow the spread and remove the melaleuca trees from the Everglades.  Millions of dollars have been spent in treatments and research.  Slowly, wetlands within the Everglades are starting to be reclaimed and restored.  You can still see thick stands of melaleuca trees if you go to the western parts of Broward, Miami-Dade and Palm Beach Counties.  Right now, the trees are in bloom and you can’t miss the smell. 

In a letter I received from the grand-daughter of one of the men that introduced the melaleuca trees to South Florida, she explained her grandfather  thought a market would develop for the oils, sometimes referred to as tea oils.  Many products contain melaleuca or tea oils, but the trees in South Florida don’t seem to product enough oil to be viable opportunity.   The wood of the tree isn’t very useful for anything but mulch.  Most melaleuca mulch is created from removing trees from wetlands, so buy as much as you need! 

Below are pictures of melaleuca flowers, leaves and mature trees. 

For More information:

Gene Dempsey, City Forester
Environmental Services
Office - (954) 828-5785  Fax - (954) 828-4745

Think before you print!