Gummosis is the result of diseases, or insect attacks where liquid (sap) oozes from a plant.
It is regarded as a secondary problem and indicates that the plant is under attack form some other source. Only by controlling the pest or disease will the gumming actually stop.
Removal of the gumming may be necessary in order to get to the problem pest.
In many cases the gumming is the plant's defence system where it aims to suffocate, or drown, the problem pest in the plant's sap.
Gummosis of conifers is also known as resinosis.
In apricots, excessive gumming with wilting and dieback is the result of "dead arm disease" (Eutypa sp.), which gains entry via pruning cuts. Control recommendations are usually to prune off infected material and burn. Spray pruning cuts with a benomyl mixture. It is recommended to contact local departments of agriculture for verification of this disease.
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