Juniper Health / White Spots

[Kedron Brook]

Hi all of yous, hope everything's growing green. First post from me. There's two parts.

I recently became obsessed and upgraded from a couple of flim-flam pot plants. Among my new collection are several junipers; Shimpaku, procumbens, Japanese. Any hot tips to keep them healthy? Regrettably my townhouse courtyard won't give them heaps of sunlight, which I feel is the biggest weakness here. Reliable watering is perhaps the biggest strength, or the fact they only come inside one at a time, during the night when I study

Main question, can you educate me about the white spots in these photos. I bought this little one cheaply, and the man at the door said it was raised from seeds he collected from a street tree. It definitely had a lot of very small scale bugs After picking at it, wiping it with wet wipes and spraying with soapy water it became five shades brighter. I've had it only two days. It remains in quarantine. I will spray again with soapy water (and the nearby plants). At least some of the remaining spots are inside the leaf. Totally impossible to scratch off. Others seem to come from the cracks between the leaves. Some other website says junipers might produce wax or resin. Is that a possibility here? What's more, do I pick a insect treatment product up from somewhere?

[shibui]

Usually white bits on juniper in spring are cones but what I can see in the photos don't look right for cones. Unfortunately the photo is not close enough to see what it is.
Is it possible to zoom in closer to get a better look?

[KIRKY]

It’s the start of a scale infestation. There is one brown adult scale in the photo the others white ones are just developing.
Not sure what you can use for Juniper as I hate them and they hate me with rashes so I don’t bother growing them. I know they can be sensitive to some treatments perhaps someone here with more experience growing Juniper will pipe in with what works. But definitely scale.
Cheers
Kirky

[Grant Bowie]

I also think its scale. You can spray with Pest Oil or Eco Oil or another smotherant.
Some People that say this is dangerous to the plant have no basis in fact to say so. The spraying is harmless to the tree and lethal to the bugs. I have found also that it prevents some spread of mildews etc.

As for Junipers they need plenty of sun, this will also help reduce risk of scale, black aphids.
Fertilise regularly to keep the tree healthy with a healthy immune system.

Grant

[Kedron Brook]

Thanks in advance Shibui.

It was fiddly work and produced several photos. I will continue spraying with the soapy solution and consider one of those Pest Oils. Thanks Bowie.

I guess it fits that it's all scale. Yet it seems odd I cannot remove all them. Other than that it might just be lack of experience, because scale might not always have the yellow egg yolk centre?

[shibui]

I guess it fits that it's all scale. Yet it seems odd I cannot remove all them. Other than that it might just be lack of experience, because scale might not always have the yellow egg yolk centre?

There is one scale that looks like tiny eggs but that's only one sort. Most are just brown shells. Some are tiny and hide down in the leaf axils, others are larger and sit on the leaves or stems.
Scales are one of the harder pests to get rid off because they hide under a hard shell so most sprays only kill the juveniles that have not developed hard shells yet. Most adults are not affected and keep laying new eggs.
Oil based sprays are effective because they coat the whole shell and suffocate the insects inside. You still need to make sure all surfaces are coated and then repeat spray a few times at week or 2 week intervals to get any you missed first time.

I still can't see any obvious scale in the new photos but some of the damaged foliage in photo 3 looks like it could have been attacked by mites. Check for tiny creatures. Tapping the branch over a sheet of white paper can help show them up. There should also be very fine webbing with mites but I can't see any signs of that either.

[Daluke]

Get a high powered jet and spray the foliage - keep in full sun.

This works on pines too -

[treeman]

I can see what looks like scale (yellow circle) and what looks like mite damage (red circle)
As mentioned, pest oil will clean up both but......
these junipers come from montane regions and need a lot of water (misting, spraying, nightly dew etc) on the leaves, full sun and constant vigorous fresh air movement to stay healthy. Keeping them too protected - (even with light over head cover) will lead to problems. They only need a little shading on the hottest, driest summer days

[KIRKY]

There is one brown adult scale in the second photo. Follow the thumb holding shoot down to where the first right hand off shoot starts it’s just there 1/8th of an inch from where it branches right.
Cheers
Kirky

[Kedron Brook]

Thanks for the help everyone

I will pick up some Pest Oil. This little one will stay in isolation. Although the east fence is the sunniest, it will only be in direct sunlight at midday onward. I can mist the plants daily, twice daily if needed.

Kirky, it's the end of the scale infestation! Definitely many bugs were on board when I bought this. Most were removed by hand with wet wipes and soap. I reckon with a fair go it ought to recover and that feels pleasant.

[Kaijose]

nice information very helpful topic

[Promethius]

I had success with Eco Oil last year. I’m sure that other oils or a surfactant would be similar in effect. This followed lots of manual labour with a scalpel and a stiff toothbrush to remove the bulk of the accessible scales.

The scales you see are an armoured life stage that is hard to disrupt with topical treatments. The crawlers, however, which are the new generation released in late spring, are more vulnerable. Repeated treatments separated by a few weeks are more likely to get the crawlers.

Keep in mind that the scale casing will still be there til it drops off, even if the organism inside is dead.

This is a useful resource, although I personally wouldn’t use systemic insecticide. https://entomology.ca.uky.edu/ef429

[Kedron Brook]

All white spots fully removed. Pest Oil was used. There was also rain on and off during the last week. I reckon it was probably the muck remaining after removing the scale bug itself.

[Kedron Brook]

This plant recovered nicely at first. Possums knocked it over a lot, until the roots were drying up. The benches were rearranged and possums vandalism is reduced.