Myrtle Rust

[Rory]

"It is also interesting that you say triforine has no ill affects on young shoots. I was using it at 20% strength initially and it killed / mutated all the brand new growth on my melaluecas as I sprayed when buds were bursting. What strength were you using? What Mel's were u spraying? How did you acquire the triforine, is there a specific brand you used that was just this or with additives?"
I've been using Yates as it is provided free to us through a sponsorship deal. I am a bit surprised that you say you have applied it at 20%! The recommended rate is 14ml per litre or 1.4%. Could explain the damage to new to new shoots!

20% strength means you make up the recommended dosage for making 1 litre of Triforine, then you add that amount to 4 litres of water. In other words, make 1 litre of the recommended strength, then add that to 4 litres of water, thus making 20% of the full strength. I then tried this method also at 50% full strength a month later, but this really knocked down the new growth at the bud stages. It isn't that bad if applied after about 3 weeks after the new growth has hardened off though.

[Peterji]

If you are using Triforine at 20% of the recommended rate I suspect it is having no effect at all and it is ongoing damage from Myrtle Rust that is causing the burning off and distorted new growth not the chemical.
With regards to the stand of Rhodamnia rubescens on my property I should of elaborated... my property is 300m above sea level on the southern rim of the Mt Warning caldera and we receive ca 2000 mm of rain per annum plus a lot of moisture from mist and low cloud, so it's quite possible that it is actually wetter and cooler in sheltered areas than the ideal range for the spread of Myrtle Rust and more exposed trees may actually provide a more suitable environment for the rust. I don't think this necessarily contradicts what you are saying about the worst affected trees being more shaded and moister in some places.

[Rory]

Yeah, no the triforine at reduced strength killed off the myrtle rust. I haven't had it come back since about March / April this year, so the combination of everything I've done has worked for me so far.
I may spray as a preventative still, but it will be interesting to see if it comes back.