I live in Murray Bridge in South Australia and have a mature Brachychiton rupestris Bottle tree. Last year I noticed some of the mature seed pods showing signs of gummosis. This year the signs of gummosis seem to be abundant and infesting the green seed pods. Any ideas on 1) What causes it and 2) How to cure it?
Brachychiton Rupestris Gumosis
Certified GKH Gardening Expert
Based on the appearance of the pods, the most likely explanation seems to be damage from insects or other pests feeding on the pods. The pest damage could then cause the gummosis and allow rot in. I am not sure of specific ways to control this unless you can find the pests that are responsible and identify them.