Armored(?) Scale on Juniper

[Srt8madness]

Need some help here, browsed other threads but still not quite sure. I have this nice lil Sabina juniper with what appears to be a scale infestation. I've used Imidacloprid to no avail

It is affecting my Sabina and chinesis sea green. My procumb and unknown variety are unaffected.

What should I do? Still pretty hot here, wait till fall and then use Hort Oil?

Pics are all of Sabina

 

[Paradox]

You said you used Imadacloprid on the trees. Have you tried scraping a few of the scale off to see if they are still alive? They sometimes dont drop off when sprayed. Also how many times did you spray? You need to treat every 2 weeks for at least 6 weeks to get all of the life stages of the scale. Not sure if Imadacloprid covers all life stages

If they are still alive, I wouldnt use horticultural oil now unless you can put the trees in absolute shade for a few days. Its not a good idea to spray horticultural oil when its hot and sunny.

 

[Srt8madness]

I used the Bonide granules. I haven't scraped any in a while but eye test says there are more than there were before. I used on the lower end of the dose.

I wouldn't look to use hort oil until it cools down. Shade isnt a problem. But would it work?

 

[Srt8madness]

I scraped some. They kind pop off. So small they just look like white specs. Some are so tiny they fit between two lines of my fingerprint.

 

[Paradox]

I used the Bonide granules. I haven't scraped any in a while but eye test says there are more than there were before. I used on the lower end of the dose.

I wouldn't look to use hort oil until it cools down. Shade isnt a problem. But would it work?

Horticultural oil should smother them. People often use Neem oil for scale.
If you are getting really tiny ones, it could be a new batch hatched as I dont think the systemic would kill eggs that have been laid.
It would only work on things actively eating the tree at the time you apply it.

How long ago did you apply the systemic? I dont know how long an application should be effective.
Scale eggs hatch in 1 to 3 weeks after being laid so if you applied 2 weeks or so ago and you are seeing new tiny ones now, it could be a new set of them hatched which is why I said you have to reapply every 2 weeks for at least a month and a half. I usually do every 2 weeks for 2 months when I am battling scale and there are too many to just manually remove.

 

[Firstflush]

I believe all the white ones are dead. You could pin prick them to see if they still have mushy insides. Crunchy dry are dead.

 

[MaciekA]

This isn't scale. It's not a pest or pathogen. It's just resin.

I don't know this juniper species, but there are several species of juniper that do this. The one I'm most familiar with, have collected before and is native to regions close to me is j. occidentalis (western juniper). These ooze resin out of their foliage exactly like this, and your photos have a smoking-gun-level textbook picture-perfect characteristics of juniper foliage resin flecks.

I would immediately stop treating this and get a magnifying glass so that you can convince yourself: these are not insects

If any of you are looking at tiny pictures on mobile devices, you should maybe look on a bigger screen at 1:1 and compare to this picture of a western juniper, which you should also look at 1:1 on a large screen (before whipping out the oils and sprays). Notice the positioning and the chunky, secretive, matte appearance of the resin flecks.

Resin flecks like these are similar to the ones you see on bristlecone pine foliage. They're not pests, they're not fungus, they're an evolution-driven defense against pests.

 

[Srt8madness]

Well shit. Thanks, that's why I posted it up. Since posting it just got a neem blast and shade, goes back into sun today. Will take out the magnifying glass and look closer. Makes a LOT of sense with the pop when scraping off.

 

[Crazy Diamond]

Yes probably they are resin spots, my Cupressus sempervirens also do that

 

[Wires_Guy_wires]

Flick a few off and heat them with a lighter.
If it's scale, it doesn't melt.
If it melts, it's resin.

 

[Potawatomi13]

Well shit. Thanks, that's why I posted it up. Since posting it just got a neem blast and shade, goes back into sun today. Will take out the magnifying glass and look closer. Makes a LOT of sense with the pop when scraping off.

Do not think neem should be in Sun either. Also an oil.

 

[Paradox]

This isn't scale. It's not a pest or pathogen. It's just resin.

I don't know this juniper species, but there are several species of juniper that do this. The one I'm most familiar with, have collected before and is native to regions close to me is j. occidentalis (western juniper). These ooze resin out of their foliage exactly like this, and your photos have a smoking-gun-level textbook picture-perfect characteristics of juniper foliage resin flecks.

I would immediately stop treating this and get a magnifying glass so that you can convince yourself: these are not insects

If any of you are looking at tiny pictures on mobile devices, you should maybe look on a bigger screen at 1:1 and compare to this picture of a western juniper, which you should also look at 1:1 on a large screen (before whipping out the oils and sprays). Notice the positioning and the chunky, secretive, matte appearance of the resin flecks.

Resin flecks like these are similar to the ones you see on bristlecone pine foliage. They're not pests, they're not fungus, they're an evolution-driven defense against pests.

Interesting
I have procumbens, shimpaku and San Jose junipers which I guess don't do this so I've never seen it to know that some juniper do ooze resin.

 

[MaciekA]

Flick a few off and heat them with a lighter.
If it's scale, it doesn't melt.
If it melts, it's resin.

Nice test. Also, if it smells kinda nice, it might not be scale either.

 

[Wires_Guy_wires]

Nice test. Also, if it smells kinda nice, it might not be scale either.

If memory serves me right - and it's been a loooong time since I've burned bugs with a magnifying glass - the chitin armor of insects smells like burned hair. But then again, they've been sippin on that juni juice. It could very well be so that they smell just like resin drops.

 

[rockm]

FWIW, spraying scale that is in shield form and cemented to trees is completely ineffective. They are mostly immune to it, since they have a waxy coating on their shells that repels liquids. Scale is only vulnerable to spray insecticides in its juvenile "crawler" phase when it is mostly a worm-like thing that hatches from an egg and goes searching for a place to metamorphose into a scale--which is a shell that covers an immobile insect beneath.

Systemics are mostly the only way (short of hand picking the things off) to get rid of scale once its mature...

My money was also on resin spots for this tree BTW...