With all due respect, I notice that most of the responses claiming the unnecessary evils of preventative chemical application are coming from our more southern members. I used to get away with this too when I lived in Sydney, but since moving further north I don't have that luxury.
In the local area where I live in northern NSW, annual average rainfall sits at around 1800mm and
annual average 9am relative humidity is near 80% - both well above say Canberra or Melbourne. Annual average daytime temps are around 26 degC, so it is nearly always warm too.
Under these climate conditions, it is near impossible rely solely on drainage, breeze and sunlight to prevent all your trees ailments. Yes, you could restrict yourself to growing species like ficus..... or ficus?, but that is not where my head is at, so I bring in the chemical cavalry by necessity.
Action Jackson wrote:
Would love to hear your approach to preventative treatment or proactive application if you like:
- what you use and purpose
- when you use it (including how often)
- how you use it
1. Daconyl - a must for pines during candle-opening through to hardening-off - otherwise needle cast is a near 100% certainty the following year.
2. Annual copper sulphate spray for general as a general fungicide.
3. Quarterly Copper fungicide application to the trunk and branches of anything with a textured or thick bark that holds moisture - the shadow cast by a dense or ramified canopy, coupled with the warmth and damp/humidity, causes fungus (as well as moss) to grow on the bark.
4. One or two applications of Cleary's 3666 in the warmer months seems to protect new buds on maples from any fungus. As well, I have never had any die back, browning, or fungus problems with Junipers since using this fungicide.
5. Locusts during summer
- these locusts have, in the past, stripped maples, elms, bougeys, figs, and even new needles on JBP's. I have tried all sorts of off-the-shelf caterpillar/grasshopper preventatives and killers, to which these locusts thumb their nose to all of them. I now nuke them twice or 3 times each summer with Rogor - it's the only thing that seems to keep them at bay.
6. The dreaded black tips and leaf curl on tridents - I have a couple of tridents inflicted with this problem since moving north, and have been systematically working through potential causes and solutions for the past 4 years. There has been a lot of debate on this forum as to the cause of this seemingly common ailment, yet no one has really put their finger on it yet. One regularly touted theory is that it is due to thrips - but I am fairly certain this is not the case. This year, I am pinning my hopes on phytopthora being the cause (as I am out of ideas if it is not phytopthora
). So, I have managed to source Aliette, and will apply to the symptomatic tridents over the course of this year.
Some may gasp in horror at the chemical munitions stored in my shed - I'd prefer not to have to use them, because quite frankly it is a pain in the rear end, and more work I could really do without. But in some microclimates, it seems a necessary evil.
