I've used it once put on a known trail that I had plenty of pics sprayed it on logs ,trees brush and a corn pile walked rt past all of it not even a look except for the corn pile so waited till the corn pile was gone and they never gave a second look after that so I would say spraying on a food source they all ready eat is not gonna to be to productive as far as knowing if it works. in my opinion it's not worth the money when they tell you to spray logs foliage and they never even gave it a glance that's my 2cent