Quince Tree With Dark Brown Bumps on Branches

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.

To readers: Sometimes the pictures that are sent to me are not the best so I have to do some "interpretation" on them. But I appreciate all pictures sent. They help alot.

A. From your description and the pictures it looks like 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.

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.

A wild guess from the picture, it might be brown soft scale particularly because you mentioned the ants.