[acn-l] FW: Exotic control success story

Jay DeLong (thirdwind at att.net)
Tue, 07 Sep 1999 22:35:25 -0700

Interesting story on biological control of an exotic species. Can kudzu be

Jay DeLong
Olympia, WA

Published Wednesday, September 1, 1999, in the Miami
Herald, Pg. 1 www.herald.com

Scientists gaining ground against melaleuca scourge

Herald Staff Writer

Powerful herbicides, crews of chainsaw-wielding
laborers and a hungry beetle have cut the number of
acres infested by the nasty pest tree melaleuca by
almost a third in the last decade, scientists at the
South Florida Water Management District said Tuesday.

The $25 million push by a state and federal agencies
has cleared the aggressive invader from Australia from
virtually all the Everglades south of Alligator Alley
-- and raised hopes for winning an ecological war that
seemed all but hopeless just a few years ago.

"It's possible now that we may be able to eradicate
it before my retirement." said Francois Laroche, 38, a
senior environmental scientist at the district. "The
key is whether we can maintain funding we need to
continue doing what we've been doing. If funding is
kept up, melaleuca might be swept out of the entire
Everglades and from the marshy edges of Lake
Okeechobee in five to 10 years.

Melaleuca is biological poison in South Florida.
Fueled by the spread of windblown seeds, melaleuca's
relentless march into the wetlands has smothered
native trees and grasses and left no room for wildlife
in vast tracts of the Everglades. The dense forests of
oily melaleuca trees are also safety threats, making
wildfires spread faster and burn hotter.

The tree -- which has flaky, light-colored bark that
resembles sheets of peeling paper -- dots older
neighborhoods where it was planted for shade in the
1950s. But it is most common in western Miami-Dade and
Broward counties where melaleuca forests have overrun
virtually all undeveloped private property that was
not faithfully tended by mowers or grazing cattle.

Agricultural researchers brought the melaleuca to
South Florida decades ago in the hope that the thirsty
tree would help dry up swamps for farmers.

No natural pests

But with no natural pests on the continent, the tree
ran amok. By the late 1980s, it looked as though dense
melaleuca forests would take over every square inch
that already wasn't covered by a house, a farm or a
shopping center.

At its peak, melaleuca covered almost a half a million
acres in South Florida, with saplings sprouting on
another 50 acres every day.

But the intensive eradication program that brought
together more than a dozen agencies has managed in the
last six years to start turning back the melaleuca tide
on public lands.

Dramatic progress has all but cleared live trees from
the water conservation areas of western Miami-Dade and
southern Broward counties, Everglades National Park,
Big Cypress National Preserve and the Loxahatchee
National Wildlife Refuge.

Acreage is down

In 1993, about 52 percent of the melaleuca in South
Florida, covering about 252,000 acres, was on public
land while 48 percent was on private property,
according to a new report published by the Florida
Exotic Pest Plant Council and edited by Laroche.
Today, there are about 137,000 acres of melaleuca on
public land and 65 percent of all remaining melaleuca
forests are privately owned.

"We still don't have any programs to do anything on
private lands," Laroche said. "That's where we hope
that the insects will help. The insects in this case
are so-called 'biological control agents' -- pests
that help control melaleucas in their native Australia.

Snout-nosed beetle

In 1997, federal agricultural researchers introduced
the first of these insects -- the snout-nosed beetle --
that is slowing the spread of melaleuca seedlings along
the eastern fringes of the Everglades. Other Australian
insects are now in quarantine in Florida, awaiting the
completion of tests that might allow them to be turned

"Biological control is our great hope," Laroche said.
"Until then, we are going to continue with our
herbicides program."

Chemical herbicides are effective but expensive. Over
the past eight years, the district, which is funded
primarily by South Floridians' property taxes, has
spent more than $6 million of its taxpayers' money on
the melaleuca war with other funding coming from
federal sources, other state programs and cash paid by
developers and other companies whose work destroyed
Copyright 1999 the Miami Herald.

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