Q: These things like spaghetti pasta were sticking out of our tree that suddenly died. They crumbled when I touched them. Did they attack the tree and kill it?
A: These are sawdust tubes pushed out by ambrosia beetles as they bore into your tree. The tubes are rarely seen this time of year. However, because of abnormal rainfall, some trees are producing ethyl alcohol, a reaction to stress. Alcohol production signals ambrosia beetles to attack. The beetles introduce a fungus into the tree, which clogs up its xylem (the water and nutrient transport system). Since your tree is already dead, it’s hard to say exactly what killed it. Its roots may have rotted or drowned from standing water or saturated, poorly draining soil. The ambrosia beetles may have merely pushed it over the edge. The beetles are not necessarily a death sentence. When numbers are low and a tree is fairly healthy, a tree can recover.
Learn more about ambrosia beetles from Ohio State University.
By Ellen Nibali, Horticulturist, University of Maryland Extension Home & Garden Information Center. Ellen writes the Garden Q&A for The Baltimore Sun.
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