Scale infestation on shimpaku juniper

[Wintermute84]

Heyy, first post. I was about to put my shimpaku juniper into the garage for winter when I noticed it has what appears to be a scale infestation. The picture included shows what's happening all over the tree unfortunately. Just wondering if anyone could suggest some kind of treatment, given that it's early December? Didn't know if certain insecticides were a bad idea in the winter. Any advice at all would be greatly appreciated

 

[leatherback]

I would use a winteroil treatment. Or an insecticide suitable for scale. Would not think about using it twice

 

[Firstflush]

Pick off bigguns, then neem plus hort soap. Many look dried and dead already.

 

[sorce]

You better give us more information before December 21st.

Welcome to Crazy!

Sorce

 

[Wires_Guy_wires]

I would use systemics.

Scale is about the only juniper pest I couldn't get rid of with safer stuff. Systemics have proven to be a once a year good option to get rid of them all.

 

[Crazy Diamond]

Yep sistemic its the best option those bastards are really tough

 

[River's Edge]

Heyy, first post. I was about to put my shimpaku juniper into the garage for winter when I noticed it has what appears to be a scale infestation. The picture included shows what's happening all over the tree unfortunately. Just wondering if anyone could suggest some kind of treatment, given that it's early December? Didn't know if certain insecticides were a bad idea in the winter. Any advice at all would be greatly appreciated

Please keep in mind that if you use an insecticide with oil or soap it is a good idea to rinse off the foliage in 24 hours so the plant can breathe again. Also some insecticides are not suitable for juniper, so check labels before using. You may need to change the dosage or product.
Scale is one of the more difficult to control insects, for a situation like that I would want to use a systemic but the time of year with dormancy is not conducive to that approach.
I would recommend a solution of soap and alcohol with q-tip application on the worst areas, if spraying then saturate above and below, get the undersides of the foliage as well and rinse 24 hours after application.
One recipe suggested is as follows: two drops of liquid dish soap one cup of warm water and one teaspoon of rubbing alcohol.
* Taken from Bonsai Today's Master Series " Junipers"
For dish soap a good choice is Dawn liquid detergent "original".

For insecticide it usually boils down to what is available to you in your location for the particular purpose.

 

[butlern]

Which among the "systemics" have individuals found effective against scale on shimpaku and RM juniper (those available in the USA)?

Specifics would be much appreciated.

 

[Firstflush]

IMHO, scale is not a real tough pest to kill. Pick what you can see and the bigger bugs off.
Get a 100% cold pressed neem oil and mix with a Castile soap and a few drops of dish washing liquid for an emulsifier.
I use Dyna-Gro neem.

 

[Wires_Guy_wires]

Which among the "systemics" have individuals found effective against scale on shimpaku and RM juniper (those available in the USA)?

Specifics would be much appreciated.

I'm using a single knock out systemic spray, a combination of two systemics containing:
lambda-cyhalothrin and acetamiprid.

Kills them dead and kills them good. It also kills every bug around it, and it causes multiple types of cancer, so be mindful in the application of these materials.

 

[River's Edge]

Which among the "systemics" have individuals found effective against scale on shimpaku and RM juniper (those available in the USA)?

Specifics would be much appreciated.

Bayer Tree and Shrub, very effective, readily available in the USA. Also available from online in the USA. Blue bottle second from left. For specific information check out the Kill List and ingredients on line. Good online site for this information is DIY pest products.

 

[parhamr]

Which among the "systemics" have individuals found effective against scale on shimpaku and RM juniper (those available in the USA)?

Specifics would be much appreciated.

Extension offices and agriculture departments of major North American universities are the go-to for authoritative, regionally applicable information. See this for example: https://entomology.ca.uky.edu/ef429

Imidacloprid works a treat

 

[Mike Corazzi]

I use this on everything. Not one scale or aphid in the time I've used it.

 

[butlern]

Bayer Tree and Shrub, very effective, readily available in the USA. Also available from online in the USA. Blue bottle second from left. For specific information check out the Kill List and ingredients on line. Good online site for this information is DIY pest products.

How are those who use Bayer Tree and Shrub metering its application?

It's granular and gets applied to the soil and watered in, correct?

Or are you all applying the diluted form of the liquid concentrate to the foliage?

Seems it comes in a couple of "flavors"

 

[penumbra]

How are those who use Bayer Tree and Shrub metering its application?

I am using Bonide granules I get off Amazon. Honestly, though I have been using it for several years, I don't meter it at all. I just use plenty.

 

[Dav4]

Whenever I see scale issues on junipers, I always wonder about the husbandry involved with that tree. I've had issues with scale on my junipers in the past. Honestly, they were probably too crowded on my benches and were kept too close to the border of the woods where scale was rampant in the indigenous trees. Also, where are you located? I'd be very wary of putting a tree with that kind of parasite load into an enclosed structure with other susceptible trees. Junipers are very cold hardy and easy to overwinter outside in most of the continental US. Finally, I wouldn't hesitate to hammer that one with a dormant oil immediately- treat your other junipers as well- and then hit it with a systemic labeled for scale in a few months as the tree prepares to breaks dormancy.

 

[Dav4]

How are those who use Bayer Tree and Shrub metering its application?

It's granular and gets applied to the soil and watered in, correct?

Or are you all applying the diluted form of the liquid concentrate to the foliage?

Seems it comes in a couple of "flavors"

I've used it before and usually guesstimate as I sprinkle it on the soil surface... maybe a tablespoon per gallon of soil. (never used it to treat scale)

 

[penumbra]

(never used it to treat scale)

I use it primarily to control scale.

 

[River's Edge]

How are those who use Bayer Tree and Shrub metering its application?

It's granular and gets applied to the soil and watered in, correct?

Or are you all applying the diluted form of the liquid concentrate to the foliage?

Seems it comes in a couple of "flavors"

The instructions on the container indicate a certain quantity for the diameter of the base of the tree and direct that it be applied within the drip line for watering in to the surrounding soil. I have simply used a fraction of the suggested amount depending on the trunk thickness of my Bonsai following the guidelines. I generally use a bit of generous measure due to the fact my inorganic soil has very little CEC capacity. And I modify my watering pattern so I am not flushing through copious amounts of water. The granules break down rather quickly and very little remains after two weeks. The active effectiveness is said to be four or five months.