Pest repellant discussion?

[WMC]

Hi all

Well its that time of year and here come the pests.
It got me wondering what the concensis is out there for what others are using to deal with common pests such as Aphids, Caterpillars, scale etc.
I took some close up pics of my most recent uninvited guests. The tiny caterpillars are new for me, ive had larger ones but nothing as small as these little guys before (and i seem to have heaps of them).

So to the point, what are people using and for the general listed pests above, and are people using 1 pesticide or a few?

I've been using eco-oil but am running out so looking for advice before restocking.
I grow mostly maples, elms, junipers but also have crab apples, flowering appricots, pines and a few other odds and ends. I got Eco-oil for my maples and just used it on anything and everything....

[greg27]

I use Neem Oil for aphids which seems to work well. Neem Oil is a natural insecticide that works on most sap-sucking pests. Someone (TimS?) mentioned in another thread something about granules for controlling aphids.

I've had heaps of little green caterpillars; they seem to have a taste for eucalypts and leptos, and hide under the leaves spinning a web. I tend to just keep an eye out for these and squish them as I see them. I had a small river red gum go through a unintentional defoliation from one of these little suckers before I noticed it.

I'm not sure what the two other insects are in your photos but just be aware that you don't need to kill everything that moves - if it's a predator insect it will help to keep away nasties like aphids.

[TimS]

I'm trialling a pelletised systemic for the first time this year, but it's bloody expensive so not going to be a cheap and easy way to deal with the problem. Any kind of soap solution should work for the aphid with good coverage enough to suffocate them, neem oil as you say, a pyrethrum based spray too is also an option.

I've spot sprayed outbreaks on plants that didn't get the systemic tablet with the pyrethrum and that seems to have knocked them on the head pretty well.

[shibui]

The photos show 2 aphids. 1 is a juvenile and the one with wings is an adult. The other is one of the 'looper' caterpillars.
BT is a natural fungus that attacks only caterpillars. It is sold as dipel. Very effective but the caterpillars must eat some of the spores in the spray so needs to be reapplied after rain or watering. BT will not affect predators or insects other than caterpillars.
Pyrethrum is also natural low toxicity pesticide that is effective for aphids and most soft bodied insects. It is a contact insecticide so you have to actually get some on the bug. Any that are hiding under leaves, etc will survive. Repeat spraying will be needed to get them.
Eco oil works in a similar way.
Pyrethrum, eco oil and neem are all broad spectrum insecticides. They will kill all the good bugs as well as the pests. Pests breed faster than predators so if you kill all the predators the bad ones can come back worse later. Sometimes it is OK to put up with low numbers of pests and wait for the predators to arrive and breed up so they can tackle the problem for you.

Systemics enter the plant and spread right through so any insect that sucks or chews will die, even if you don't spray on all surfaces. There is some evidence pointing to problems with non target species like bees where it is thought they get it from the flowers. Systemics are very effective but have been banned in many places. Use with extreme care.

Thumb and finger can be very effective on smaller numbers. No chance of building immunity. No harm to non target species and completely non toxic (except to the pests).

[juan73870]

I never realised aphids grew wings like that. Learn something new every day!

Sent from my moto g(6) plus using Tapatalk

[terryb]

BT is a natural fungus that attacks only caterpillars. It is sold as dipel. Very effective but the caterpillars must eat some of the spores in the spray so needs to be reapplied after rain or watering. BT will not affect predators or insects other than caterpillars.

Although I normally just remove them by hand from my small trees, this works well for me in controlling webbing caterpillar on garden Myrtus and the caterpillars that attack tomatoes.

The roses are the first to get aphids at my place but I will just hose them off if I get too many and wait for the predators to move in. Generally takes around 2 weeks until I start noticing aphid mummies https://www.ausbonsai.com.au/forum/view ... id#p249046. I rarely get aphids on my potted trees but will hose off and move some parasitised aphids to the area to take care of the rest. The ladybugs have also moved in early this year.

[MJL]

I have a relatively small collection so reading glasses combined thumb and fingers are good. Along with rotating pest oil and nature soap every second week or so.

Strangely enough .... sometimes in the early morning and evening I find myself giving a light spray of mortien or something similar from a distance. I started going this when I was spraying under my outdoor table for flies and mozzies before my lily white legs got eaten and I’ve noticed no I’ll effects on my plants but generally less pests.


Sent from my iPhone using Tapatalk

[SuperBonSaiyan]

I'm just reviving this thread to ask a question about aphids and pyrethrum.

I previously sprayed one of my Japanese-maples with pyrethrum because there were quite a few aphids on the tree. Unfortunately, the pyrethrum burned the leaves (they turned black and crinkly). Is this to be expected with pyrethrum? Or did I just apply it too generously?

I still have pyrethrum, and just spotted some aphids on another Japanese-maple. Should I try to apply sparingly? Or should I try a detergent liquid spray? Would this be more harmful to the tree?

[TimS]

Personally I just put plain water and a good squirt of Dish washing liquid in a 2L sprayer and go to town when it comes to aphids and especially with JM. I have had similar issues spraying chemicals on them and burning foliage, so now it’s that or I have some pelletised systemic insecticide too that goes in the soil and is taken up by the roots, so when they feed on the leaves they ingest that.

Spraying with the dishwashing liquid much easier and quicker though. Did it on my Murasaki Kiyohime recently with no ill effects at all

[shibui]

I've never heard of pyrethrum burning leaves. Mixed at the recommended rates it should be fine. Any chance something else may have caused the problem? We tend to connect 2 unrelated but obvious events while ignoring other factors that may have contributed.
Pyrethrum is a contact pesticide so you need to thoroughly coat all surfaces to make sure you hit all the aphids. Spraying lightly is likely to leave a few alive.
Soapy water can be effective but you do need to do it regularly or they just come back.

[KIRKY]

I used confidor on aphids when they had their premixed green spray bottle one season on a Japanese Maple forest it was infested with aphids the worst I had ever seen that year. The following day all the new growth was shrivelled and dead. The forest never recovered. Out of 11 trees only 2 of the larger trees survived. It was a ten year old forest planted on a slab. The only treatment the forest got was confidor, then water to try and wash off the confidor followed by Seasol. Needless to say never used confidor on bonsai trees after that, and yes I know they don’t sell it anymore. My point is I would not use anything too harsh on new Maple growth again. Diluted eco detergent and water as a try on a bit of growth as a test. If the leaves react don’t use it.

Cheers
Kirky

[Robsterios]

My mate uses Rose Shield on everything, from Maples to Pines and Natives. Although I do have some, have yet to use it. He swears by it as it's broad spectrum and covers both insects and fungal. Also apparently systematic so must get into the sap. The reason I haven't used yet is as mentioned above about killing all the good guys and I too am concerned about damaging the tender opening foliage of Maples at a time when the aphids are sucking on them. I generally use Pyrethrum and this helps with aphids and I only spray lightly due to my concern regarding damaging tender foliage.

[HarleyD]

I've never heard of pyrethrum burning leaves. Mixed at the recommended rates it should be fine. Any chance something else may have caused the problem? We tend to connect 2 unrelated but obvious events while ignoring other factors that may have contributed.
Pyrethrum is a contact pesticide so you need to thoroughly coat all surfaces to make sure you hit all the aphids. Spraying lightly is likely to leave a few alive.
Soapy water can be effective but you do need to do it regularly or they just come back.

I used a pre-mixed yates pyrethrum product on some of my JMs that were being attacked by aphids last year and the same thing happened to me. The trees that I sprayed dropped most of their leaves and didn't grow them back. I've resolved to look for something else to use on my JMs since. I will be trying the soapy water this year i think!