Experts try to save stricken palm trees
By CATHY ZOLLO
SARASOTA -- Carl Meyer's house in Sapphire Shores, Villetta
dell'Palma, is named for the palms planted when it was built.
Meyer, a real estate agent who has lived here for a decade, knows what
his trees should be doing and when.
So he took note in May, when some of the thick trunk Canary Island
date palms that line his property -- and for which this neighborhood
is known -- yellowed, turned brown and died.
"I could definitely see the fronds drying up and dying when they
shouldn't be," he said, "which was a sure sign we had problems."
After DNA testing of diseased trees, palm experts in Fort Lauderdale
told the city that the problem is lethal yellowing disease, which
wiped out coconut palms in the southern tip of Florida in the 1970s.
Officials do not know how it got here. It was first identified at the
Sarasota-Bradenton International Airport and later in Sapphire Shores,
where there is a concentration of the plants it attacks.
It is possible that lethal yellowing or the insect that carries it
reached the area via infected trees planted at the airport or arriving
in cargo, said David Daberkoe, an arborist who works for the city.
The disease was also found about a month ago in south central Manatee
The city's urban forestry experts say they have only seen it in
Sarasota at Sapphire Shores so far. They hope to keep it isolated and
are trying to save 156 trees with a series of antibiotic injections.
So far, 18 trees have been removed. And the antibiotic injections will
also help keep the disease from spreading, they say.
Lethal yellowing causes trees to prematurely drop their fruit. Then
the lowest fronds turn brown. Finally, the youngest fronds are
affected, killing the tree.
The time it took to diagnose the disease slowed down the effort to
save the trees. Leaf samples sent to the lab were not enough to pin
down the culprit, bacteria carried from tree to tree by the
planthopper Myndus crudus, a locustlike bug that drinks the sap of
palms. In the process, it also spreads lethal yellowing disease.
It took DNA testing by scientists who deal with such problems farther
south in the state to identify the palm disease, which is new to
That the trees in Sapphire Shores are drought-stressed does not help,
so city foresters are telling people to pay special attention to the
palms by fertilizing and mulching them. Recent rains should help
because watering moves the drug more quickly through the plants.
On Tuesday, city foresters were making the rounds again, sterilizing
drill bits before treating each tree, tapping a modified bullet casing
into each before delivering the injection with a hypodermic needle the
size of the ones used on cattle.
"It's a preventative," said Michele Russo, a forester for the city.
"There is no guarantee that if the disease is present in this tree it
won't die, but it may slow down the process."
This is the third injection in three weeks for these, an effort to
protect not only them but also others.
"If you do get an infected one in the area, and it's not treated, it's
a bank for the insect to pick it up," said Don Rainey, Sarasota County
The trees in Sapphire Shores are also affected by a similar disease
known as Texas Phoenix palm disease that is treated in the same
manner, though experts are not sure how it travels from tree to tree.
Once a tree's flag or spear leaf -- the youngest emerging frond --
dies, it is too far gone to save, Russo said.
Those are ripped out and sent to the city dump.
"It hurts when we have to take them out," she said. "There's so much
wildlife that uses these trees."