Slime flux is a bacterial infection which causes foul-smelling sap to ooze from affected parts of the tree.

The bacteria infect the heartwood of a tree, causing the sap to ferment. The gases produced by the fermentation build up pressure which cracks the wood and forces the bacteria-laden fermented sap to flow (flux) from the fissures.

The oozing sap creates unsightly streaks on the tree when it dries. It also attracts insects, which can further damage the tree, and spread the bacteria from contact with the flux. The fissures and wounds from which the sap oozes will not heal. As the disease progresses, the tree may lose its ability to deliver water to the leaves, causing wilting and scorching of the leaves.

There is no chemical treatment for slime flux. Affected limbs and branches should be pruned below the infected area. Infections in the trunk should be tapped to allow the wet wood to drain, and to relieve internal pressure. Tools must be sterilized with rubbing alcohol after each cut or penetration to prevent spread of the bacteria.