Saving our old eucalyptus tree.
Hello. Our tree over the last six months, as been dropping dead limbs so we have started cutting back dead limbs before they drop. We have also noticed what appears to be a fungi on the outside of trees that were are treating with eucalyptus which more recently appears to be eliminating the fungi. is there any more we can do to help the old tree Regards David
Certified GKH Gardening Expert
From what you describe, it may be Armillaria root rot, a common fungal disease. Symptoms include decline in tree health, susceptibility to pests and die-back, canker on the lower trunk and mushrooms at the base of the tree.
This is bad news for you and your tree. Unfortunately there is no definitive cure. And at an advanced stage of infection and decay of the roots and root crown at the base of the tree, considerable loss of conductive tissue has occurred and will limit uptake of water and nutrients, and therefore cause die-back/limb loss and susceptibility to pests and foliar diseases.
An all-out effort to save the tree could get expensive, and is not a sure thing. I suggest soil testing and prescription of mineral and biological amendments based on nutrient deficiencies found. This would not insure a cure, but would help to give the tree the best possible conditions to resist advance of the fungus.