Which statement about forest diseases is incorrect?

Annosum Root Rot, caused by the fungus Heterobasidion annosum, is indeed associated with specific soil conditions, but it is primarily known for being prevalent in well-drained soils rather than heavy-clay soils that are poorly drained. This disease typically thrives in acidic and well-aerated soil environments. Poor drainage conditions can lead to different stressors and complicate the disease dynamics, making the statement about its association with heavy-clay soils incorrect.

Pathogens being naturally occurring in forests is a true statement; forests contain a diverse array of microorganisms, including fungi, bacteria, and viruses, which can lead to diseases in trees. Additionally, effective management practices, such as thinning, selective logging, and proper tree planting techniques, can help control certain forest diseases, making that statement accurate. While many diseases can be mitigated through management strategies, not all forest diseases are preventable due to various factors such as environmental conditions, host susceptibility, and pathogen variability, reinforcing the idea that the statement claiming all diseases are preventable is incorrect.