Q. We have a 3 year old Quince tree which looked very good
to me until today when I notice brown/dark purple small pee size bumps on the
top branches. Removing the bumps causes a fluid to ooze out. I guess the fluid
must be sweet since there are ants running up and down the branch.
it might be one of the scale insects. I have never seen scale insects on quince
in the Las Vegas valley but they do infest trees in some other climates.
Scale
insects, particularly the soft scales, will exude a sugary liquid that drips on
limbs and leaves and attracts ants. They are easy to squish and act just like
how you are describing it. There is an insect under the harder outer shell.
Young are produced by the female and they leave the protection of the females
shell, move about and find a new home where they can suck plant juices and also
build a protective shell on the outside of its body.
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| Soap sprays that are manufactured for plants are safer to use than mixing your own. |
The usual method of
control is using horticultural oils and spraying the oil on the plant to
suffocate the insect. If you are lucky enough to see the young emerge and start
looking for a home most any spray will kill them including soap and water
sprays like Safers insecticidal soap. But you will have to spray the oils and
soap and water sprays through the year to get them under control. Once under
control an oil spray in the dormant season such as winter months when it is
warm should help keep the populations reduced.
scale particularly because you mentioned the ants.