What is a key indicator of root rot in trees?

Leaning of the trunk is a significant indicator of root rot in trees, as it often occurs when the root system is compromised. Root rot typically affects the structural integrity of roots, making them weak and unable to anchor the tree securely in the ground. As the roots decay, the stability of the tree is compromised, which can lead to the trunk leaning or tilting noticeably. This physical shift not only indicates a potential issue with the roots but also poses a risk for the tree's overall health and stability.

Other symptoms like yellowing of leaves, flaking of bark, and deep cracking in the soil might indicate various health issues but are less directly connected to root rot. Yellowing leaves often suggest nutrient deficiencies or other diseases, flaking bark can be a sign of environmental stress or insect infestation, and deep cracking in the soil may relate to soil moisture issues rather than specifically to root rot. Therefore, leaning of the trunk stands out as a more direct link to the presence of root rot and the structural failure of the tree.