Timing of treatment for juniper scale

I have several Shinpaku junipers with scale. I want to spray with neem oil and/or insecticidal soap when the crawling stage is out and about and susceptible, but don’t know the timing, as in how to know when the crawlers are present. Does anyone know season/time of year where spraying can be reliably effective against crawlers and eggs? I know that it won’t impact the adults underneath their overlying scale barriers (though I have tried, regardless).

I treated my severely infected juniper in the spring time. I treated this particular juniper ~2 years ago and haven’t seen any signs of reinfestation My course of action:

  • Scrub ALL foliage on the tree using a toothbrush. I went through every piece of foliage all across the tree and basically scrubbed off all the scale (it was a really significant amount and took a lot of time).
  • I repeated this about 2 weeks later as a second pass to eliminate more scale.
  • After each scrubbing with the toothbrush I also sprayed with an “insecticide” that was water, dish soap and a touch of isopropyl alcohol in an effort to choke the bugs.
  • Follow up with lime sulphur spray 2x times (once in the mid fall, once in mid winter) to eliminate overwintering possibilities

You can see some before/after photos on this other thread about scale - Juniper Chinensis Scale - #3 by Bhugs

May I asked your dilution rate for the lime sulfur application? My label is in 100 gallons batch’s,

I worked it down to 5 oz per gallon but I wanted to see if your rate was similar.

Thanks!

I go by a 20:1 to ratio of water/lime sulphur. So I’m 50mL for a 1000mL which I usually do in a small hand held spray bottle

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