80oz/100 gl is the correct rate for Merit 2f. We inject at the base and go out from there at 3 foot intervals in a grid pattern. Inject at 1Q per inch DBH (a 15" tree recieves 15Q of the mixed product. I have been using this rate for many years as per the product label.
Mreit 2f can also be used as a foliar treatment, but at a much lower rate. This treatment is done at 1.5oz/100gl. It is a great substitute for TalstarOne, Scimitar or Acephate.
What is nice about Merit 2f is that it is in a flowable form, which makes mixing alot easier. The 75 WSP comes in those nasty water soluble packets. If you need to only mix up a small amount, the package can become very messy. With the flowable, you can mix up what ever amount you need with little trouble.
One other note. The flowable can be very expensive. Depending on what vendor I use, it can run from $800.00 per gallon to $1200 per gallon.