Gummosis

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Gummosis is when a sticky gum oozes from the bark of some trees, especially fruit trees. It happens as sap leaks from wounds or cankers in response to stress such as frost, injury, disease, insect damage, or other damage. The gum forms under the bark and then seeps out between the bark plates on branches or the trunk. It is made of sugars and acids. Gummosis is usually linked to problems with the tree’s water balance and overall health. Frost, injuries, and infections by bacteria or fungi (like Armillaria) can worsen gum flow.