Ambrosia beetles are common, tiny (only about 1/16” long), and can infest hundreds of different woody plant species. In South Carolina, these little beetles typically infest stressed trees, vines, or shrubs. Females will bore into stems and branches, creating a gallery. Beetles carry fungi on their bodies, and this fungus then grows inside the galleries, often appearing as white, gray, or black. The beetles feed on the fungus that grows inside the galleries.
Most ambrosia beetles are secondary pests, meaning they only attack and impact plants that are already stressed (e.g., from frost damage, flooding, drought, or poor planting). For this reason, proper tree and plant care is essential to prevent ambrosia beetle damage. When ambrosia beetles attack, they often leave characteristic spaghetti-like projections coming out of the host. These projections are called noodles, frass tubes, or toothpicks and are made mostly of sawdust, beetle frass (poop), and some fungal mycelium. These are sure signs of ambrosia beetle infestation. In South Carolina, the granulate ambrosia beetle is one of the most common species that attack woody plants on landscapes.
Some species of ambrosia beetles are primary pests, meaning they can and do attack healthy trees. The redbay ambrosia beetle attacks all species in the family Lauraceae, which includes redbay, swampbay, avocado, and many others. This beetle carries the disease laurel wilt, which is responsible for killing millions of trees across the Southeast. The black twig borer is common throughout the state but especially in the Lowcountry. This is one of the smallest ambrosia beetles and creates its galleries in small twigs. This damage causes branch flagging, which can reduce the aesthetics
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