How to treat Juniper Scales?

I noticed I had these white specs on my juniper and within a few days it seemed like a lot more showed up! After two weeks this branch had started to fade. Luckily it wasn’t a major branch in the design so I chopped it off. There’s still a few branches with some scale infection and I’m wondering how do I treat it immediately so that I can save my tree? Please help!

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Imidacloprid (Bayer) or dinotefuran (Safari) should do the trick. Safari is much more expensive, so I would start with imidacloprid, but if that doesn’t work, or the scale (or other pest) become resistant, switch to Safari.

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I posted on another forum and someone had said that Bayer wouldn’t be as effective as it’s best applied in the fall. Thoughts?

Imidacloprid (most popularly by Bayer, but also Bonide and in Bio Advanced 3-in-1 spray) its one of the most commonly used insecticides. Both it and Safari are systemic, and work anytime, but most apply them mid to late spring after trees have leafed out. Both can harm bees, so flowering trees when flowering shouldn’t be exposed, but otherwise their use is fine. Perhaps the recommendation to use in fall is so it will be in the tree’s system over winter and early spring, but otherwise, I don’t understand the logic.

…but, scale can be tough, especially armored scale, so you may have to try different things.

I also use a product called Drench. It’s a systemic like Bayer 3:1 without the fertilizing component.

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I have used a mix of Lime Sulphur, Horticultural Oil and Water to deal with scale on trees. But I haven’t had to do this on junipers.

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Thanks chuck! Yeah I think there was hesitation of how effective it would be against armored scales. I bought the BioAdvanced 3in1 and plan to spray it on the juniper needles. I’m not sure if it will work against the armored scales but I think I see some crawlers so I can at least kill those. Thank you so much for all the info!

I’ve used it successfully against juniper scale before. See what happens. If it doesn’t work, try Safari. It’s not cheap, but good to have on hand.

Great thank you! I only have one juniper and started collecting bonsai recently. 4 trees total so if I can refrain from buying Safari I will. If I have to get it to save my juniper though then I’ll do that… and then maybe that will be incentive to buy more junipers hehehehe

The white specs probably are not scale. Scale is on the limbs, usually, small 1/6" gray /brown rounded warts. There are other kinds, too.
This may be spider mites, wooly aphids, or some other bug. If it is indeed spreading, I would hand pick or use folier sprayed acephate. Look at your other trees, especially leafy annuals.
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Imidacloprid will do the job on scale, etc. Takes a while to notice effects. The bodies dont fall off… AND imidaCLOprid is carcinogenic… best used after flowers are gone. Will cary over to next spring.
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However one tree… hand scraping scale bodies or tweezers plucking the fuzzy white aphid masses would be faster and much more FULFILLING… smish em. Keep it simple. Less is better. And safer.
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The bug came from somewhere… with a new tree?
Check your surroundings. My landscape maples were INFRSTED with scale 2 years ago. Aphids this year…They jumped to my bonsai… breaking out the nuclear option on their sorry little a…!
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Oh the joy! Bonsai On!

Like Kurtp said hand removal is the best direction for everything if possible, saves killing what you can’t see or understand especially this time of year, pruning bad areas out and hand removal doesn’t actually take that long with a tooth brush or plastic bristle brush, I’ve got some on a sabina juniper and would rather loose a few fine shoots from scrubbing than the eco system in,on and around the tree.

If you go down the spraying root make sure it’s kept out the sun for week or so :+1:personally I’m trying removel by hand on mine and will use a lime sulphur spray in winter as a preventative treatment , good luck

This is almost certainly scale, and a pretty nasty outbreak. What treatment did you go with, and how has it worked out?

You’ll probably want a systemic like Imidacloprid, although Master Ryan-san said some scale has become immune to it. I’m dealing with an outbreak myself, and am trying Imidacloprid on one, and a very small amount of an insecticide that contains Dinotefuran on another (less important one).

The recent video on juniper scale is well worth a watch: https://live.bonsaimirai.com/library/video/scale-insect-identification-and-treatment