Q. I have an ornamental Eucalyptus tree in my back yard that
is 20′ tall and facing west. It has been steadily losing leaves and
branches the past two years. There is a black sap that has been oozing
sap through the bark. It crystalizes into a hard substances. Can you provide
a diagnosis and treatment?
is 20′ tall and facing west. It has been steadily losing leaves and
branches the past two years. There is a black sap that has been oozing
sap through the bark. It crystalizes into a hard substances. Can you provide
a diagnosis and treatment?
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| Not the readers, but this is a eucalyptus and many have a similar form. |
A. Your description of this problem about your Eucalyptus bothers
me. The loss of leaves, the branches dying back coupled with black sap that
oozes through the bark is a very good sign of Eucalyptus borer.
What does Eucalyptus borer look like?
me. The loss of leaves, the branches dying back coupled with black sap that
oozes through the bark is a very good sign of Eucalyptus borer.
What does Eucalyptus borer look like?
To my knowledge, this insect is not
been reported in southern Nevada. It has caused a lot of destruction in
Eucalyptus in California.
been reported in southern Nevada. It has caused a lot of destruction in
Eucalyptus in California.
I am paraphrasing now from California information:
“Holes in the bark and stains or
oozing liquid on limbs or trunks are common symptoms of longhorned borer
damage. When this borer is a problem, leaves can discolor and
wilt, and limbs can die
back.”
“Longhorned borers usually attack
stressed or damaged plants, leaving vigorous, appropriately watered trees
alone. In California, however, many eucalyptus trees are seasonally water
stressed during hot summer months, rendering a significant proportion of them
susceptible to beetle attack. Tree species with some resistance to these wood
borers can produce copious amounts of resin in response to an attack.”
stressed or damaged plants, leaving vigorous, appropriately watered trees
alone. In California, however, many eucalyptus trees are seasonally water
stressed during hot summer months, rendering a significant proportion of them
susceptible to beetle attack. Tree species with some resistance to these wood
borers can produce copious amounts of resin in response to an attack.”
“Extensive larval feeding beneath
the bark can spread around the entire circumference of a tree, girdling, or
completely removing a strip of bark from, the trunk. Trees at this stage of
infestation have a thin canopy with wilted or dry leaves, and the bark is
cracked and packed with larval excrement. Infested trees usually die within of
a few weeks of girdling, although resprouting can occur from the tree base.”
What does this borers damage look like?
the bark can spread around the entire circumference of a tree, girdling, or
completely removing a strip of bark from, the trunk. Trees at this stage of
infestation have a thin canopy with wilted or dry leaves, and the bark is
cracked and packed with larval excrement. Infested trees usually die within of
a few weeks of girdling, although resprouting can occur from the tree base.”
What does this borers damage look like?
If you believe this could possibly
be the problem I would hope that you would contact the Nevada Department of
Agriculture and start asking some questions.They might ask you to send up
samples Carson City for identification by the entomologist. This borer usually
attacks trees that are not getting enough water or are not being watered often
enough or both.
be the problem I would hope that you would contact the Nevada Department of
Agriculture and start asking some questions.They might ask you to send up
samples Carson City for identification by the entomologist. This borer usually
attacks trees that are not getting enough water or are not being watered often
enough or both.
Nevada Department of Agriculture in Las Vegas: 702-486-4690