Newsletter
September 2014
P
alm trees symbolize the
tropics in the public
imagination. Palms swaying
in the breeze adorn advertisements
for Florida's beaches and resorts.
As landscape plants, palms are
valued for their unique shape and
the intricate texture and form of
their leaves and stems. Their
variety, beauty, and adaptability
have made them some of the most
prized landscape plants in the
warmer areas of the state. Despite
their durability and adaptability, a
number of diseases do affect palms
in Florida.
Serious disease of palms has made
its presence known in south
Florida, where palms are a
dominant part of the landscape.
One such lethal and incurable
disease is caused by a fungus,
ganoderma zonatum, which
invades the base or butt of palm
trees up to a height of three to four
feet above the ground. Ganoderma
butt rot affects mature palms. The
disease was first discovered in
Florida in 1994 and in only a few
years it has spread to infect palms
throughout the state. At this time, it
cannot be said with certainty that
there are any palm trees resistant to
ganoderma butt rot, but we do
know that Queen palms and
Coconut palms are very susceptible
to the disease.
The ganoderma zonatum fungus
most often invades a palm tree by
means of a wound at the base of the
tree. The fungus then begins to
rapidly work its way through the
tree’s butt area essentially rotting
the wood from the inside. Once the
fungus has worked its way through
the center of the tree to the surface,
it forms a fruiting body called a
‘conk’, a spongy, whitish mushroom
-like growth which grows to form a
horizontal disc extending out from
the bark.
Unfortunately, there is currently no
effective treatment for ganoderma
butt rot. By the time the conk has
appeared on the bark, the tree is
effectively dead and must be
removed. Removal takes extreme
care to avoid spreading the fungus
airborne to other palms. Tools used
and clothing worn must be
sterilized all to avoid spreading the
disease. Once the diseased palm
tree is removed, another palm tree
cannot be planted in the same
l ocat i on wi thout ext ens i ve
sterilization and replacement of the
diseased soil.
It is important to avoid injuries to
the roots and trunks of palms to
avert the possibility of creating a
wound which may permit spores to
infect a palm tree. Periodic
observation and quick removal and
proper disposal of diseased palms
are the major methods of fighting
this devastating disease. Direct
your gardening questions to
Brickman agents at 561-626-7466.
Palm Diseases—Ganoderma
Landscape
- Hendry County Horticulture News UF
