The last few years my champaka trees have been attacked by something every winter. I’ve tried opening up the trees for more air, cutting back dying branches, wood vinegar, some microbial sprays, hosing down the white fluff, and some some good for everything enzyme/hormone type of products. Looks like whitefly to me, and I’ve looked for ants going up and and down the trunks. Some, but no obvious ant highways. Although I haven’t seen any flying insects the swiftlets circle over the trees eating something when it is at it’s worst. Can anybody help to identify the pest or offer some more things to try? I would be willing to do a severe pruning, but it hasn’t been my first choice. Upper branches still look good. Thanks for any help.

What makes you think this is a pest?  I can't really get a close up with the low resolution photos, but it appears to be a superficial fungal or epiphyte growth (lichen).  If there are no signs of damage, decline, die-back, then relax and realize that trees are a host environment to multiple organisms and usually a complex ecosystem on their own.  Stop applying all kinds of substances that may suppress the very biome that keeps pests and pathogens under control. 

 

If you really think that this is more than an obsession with a cosmetic issue and that a damaging pest lor disease is present, post or preferrably email me high res photos and photos of the entire tree and site with description of the damage that your perceive being done. don