1) Liqiud application of Trimec will be effective in 30 minutes, never used dry but if applied properly should be in that range.
2) do a search on the word "spray" in the subject area. You will get over 2 dozen threads and over 100 comments. This subject has been discussed so much in the past, you will get a lot more info by searching than asking the question again.
North central Indiana
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