Talstar P (Talstar One) should be applied at 1 fl oz per gallon of water so 30 fl oz per 30 gallons of water.
No, unfortunately Talstar P (Talstar One) is not labeled for application directly into a vent as this could result in the insecticide making its way through your air vents and you could possibly inhale the product and breathe it in. If you feel that roaches are coming from your neighbor's apt we would suggest using a bait right outside of your vents. You could use Maxforce FC Magnum or any of the other excellent roach bait gels that we sell.
A good treatment of Talstar should help do the trick. However, if the junipers are really thick, then you need to apply quite a bit for the product to get down to the ground where the bees are nesting.
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