Oak Wilt Spreading Fast
in Southeast Palos Park
Residents living in the
area south of 123rd Street, and east of 84th Avenue
need to be aware of Oak Wilt disease. The disease is spreading quickly
through this part of Palos Park.
All species of oaks are
susceptible to Oak Wilt; however trees in the red oak family (e.g., black,
red, pin, and scarlet oaks) typically die within 1 year of the fugal
invasion. Red Oaks often die in less than one month after symptoms appear.
Evidence of Oak Wilt will
appear at or near the top of the tree. Leaves turn dull green, bronze or
tan, beginning along the tips and leaf edges. Leaves at branch ends will
begin to fall soon after symptoms appear. This evidence may be confused
with the damage to the oaks already caused by the cicadas earlier this
year. Discoloration and defoliation will progress throughout the crown
within weeks as twigs and branches die. Total defoliation and death will
transpire over a short period of time, sometimes leaving crinkled leaves
clinging to limbs throughout the winter months.
Oak Wilt is caused by a
fungus (Ceratocystis fagacearum) which clogs the vascular system of oak
trees preventing the flow of water and nutrients. Red Oaks are more
susceptible than members of the White Oak family because they do not have
the ability to produce tyloses or vascular plugs which White Oaks create to
contain damage from the disease. Although White Oaks have a natural defense
system against this disease, the process is only slowed and not stopped.
White Oaks may live for years fighting off the fungal invasion, however
they act as a carrier for the spread of the disease.
Oak Wilt is spread mainly
two ways, through insect transmission and root transmission. The main
culprit in the spread of the disease is the Nitidulid beetle. The beetles
transfer fungal spores attached to their bodies as they move from tree to
tree. Severely infected trees and stumps should be removed immediately to
stop the transmission through connecting root systems from neighboring oak
If caught early, Oak Wilt
can sometimes be controlled with certain fungicide injections. Trenching or
chemically killing roots between diseased and healthy trees can prevent
transmission through root grafts. Although no treatment is a guarantee for
success against Oak Wilt, any precautions taken to preserve an oak helps
contain the disease and stop the possible infection of surrounding healthy
oaks. If you are concerned your oak may have Oak Wilt contact a private
tree contractor with a certified arborist on staff.