What is one consequence of an infestation of Asian longhorned beetles aside from dieback?

The presence of Asian longhorned beetles in an ecosystem leads to significant changes in tree health and physiology. One notable consequence is the oozing of sap from infested trees. This occurs as the beetles burrow into the wood, creating wounds that disrupt the tree's vascular system. The damage results in the tree unable to contain its sap, causing it to seep out from these openings. This sap loss not only indicates that a tree is stressed and unhealthy but also serves as a potential attractant for other pests and pathogens, further complicating the tree's overall health.

While the other choices detail outcomes that might also be associated with tree health and pest infestation, the direct and observable result of beetle activity tends to be the oozing of sap, serving as a clear signal of the tree's distress. Thus, recognizing this symptom can help in the early identification and management of Asian longhorned beetle infestations.