Answer: What you have are spittlebugs, leafhopper-like critters that produce a wasteproduct in the form of bubbly foam. Insecticidal soaps will take care of the problem. I know of no one product that takes care of bugs, weeds, and fertilizing all at once for raspberries. Especially with edibles, it's always wise to use minimum sprays and when they are needed, use what is exactly right for the problem.
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