Bacterial wet wood or slime flux, caused by many common genera of bacteria, affects many mature shade trees, including live oak, elm, and maple. Bacteria such as Clostridium, Bacillus, Enterobacter, Klebsiella and Pseudomonas gain entry into older trees through wounds such as those created by birds and human activities (mowers, weed eaters, nails, flower hangers). These bacteria use the tree sap as a nutrient source, and in doing so an anaerobic (low oxygen) environment within the tree is created, resulting in methane production, increased sap pH and an increase in pressure. Although these bacteria rarely kill the tree, the value of the wood of the tree is greatly reduced as the resulting lumber is discolored and unsightly.
Symptoms: Dark, wet, vertical streaks can be seen on the bark near or at a crack or wound. A white, slimy or foaming liquid that smells foul will ooze out of the cracks and run down the tree. With severe cases of bacterial wet wood, the health of the tree may decline, resulting in yellowing of leaves, premature leaf drop and/or branch dieback.
Management: The best way to manage the disease is to protect the tree from environmental stresses including drought, soil compaction, overwatering and mechanical damage. Special care should be taken while mowing and weed eating. Avoid installing nails or hooks that are used to hold birdhouses, flower baskets and hammocks. As with most plant diseases, prevention is the best strategy!
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|Shade Tree Disease Factsheets|
|Bacterial Scorch of Landscape Trees||Damaging Insect and Disease Pests in the Southern United States|
|Diseases of Hardwood Trees (Purdue University)||Laurel Wilt (USDA Forest Service)|
|Shade Tree Disease Management Resources|
|Forest and Shades Tree Pathology Blog||Louisiana Plant Pathology Blog (Archives only)|
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