Q.What Are The Signs Of Eucalyptus Trees Becoming Stressed And Diseased?
Hi there! I have three eucalyptus trees that are fully mature and are growing into each other. There are two trees budding up against each other and one of the trees is leaning against the house a little from it’s top branches. The other tree looks like it has dark brown spots or blisters on its trunk. The other two have bark brownish black bark underneath it’s white tree bark. How can I tell if they are cowarding each other to the point that they are becoming stressed and possibly diseased?

Certified GKH Gardening Expert
The one closest to the house is too close and could cause some problems with plumbing, not to mention it could topple in a windstorm. You may consider removing it. Plus eucalyptus trees are fire hazards.
The dark brown beneath the wood could be a sign of Phytophthora fungus. Also be wary of insect invasions from wood boring insects. These articles should help:
https://www.gardeningknowhow.com/ornamental/trees/eucalyptus/eucalyptus-tree-problems.htm
https://www.gardeningknowhow.com/ornamental/trees/eucalyptus/eucalyptus-tree-leaking-sap.htm
https://www.gardeningknowhow.com/ornamental/trees/eucalyptus/eucalyptus-tree-diseases.htm
https://www.gardeningknowhow.com/ornamental/trees/eucalyptus/eucalyptus-fire-hazards.htm
https://www.gardeningknowhow.com/ornamental/trees/eucalyptus/eucalyptus-tree-root-damage.htm
https://www.gardeningknowhow.com/ornamental/trees/eucalyptus/peeling-bark-on-eucalyptus.htm