By Gborland71
Australia 
Can you please provide some advise with regards a powdery yellow deposit on some trees in my garden. Not sure what the species in but both are the same and next to each other . I've attached a photo. Thank you , Jill
26 Nov, 2017
Answers
It looks like rust in the photos but Gb. describes it as a yellow powder which could be pollen from the flowers?
26 Nov, 2017
https://en.wikipedia.org/wiki/Uredo_rangelii
Probably the only option would be to eradicate and burn the infected plant ?
Apparently it is spreading throughout your part of the world .
26 Nov, 2017
The spores of myrtle rust are yellow like pollen, Bulba. The giveaway is the distortion of the leaves, and the pustules.
Jill, I found this, from New Zealand:
http://nzppi.co.nz/documents/pests/MR-Fungicide-Treatments.pdf
I hope it helps! :)
27 Nov, 2017
Bad news, Jill, it looks like Myrtle Rust (Uredo rangelii). I found this on it:
http://www.abc.net.au/gardening/stories/s3177618.htm
but I still don't know the best way of managing it.
26 Nov, 2017