Answer: Insects such as aphids, scale insects, weevils, Japanese beetles, mealybugs, and treehoppers are common pests of cranberry bushes. The positive part of planting native plants is that they serve as food/shelter for local critters. The downside, is that they attract local critters who enjoy munching on the foliage. I would tend to allow the natives to enjoy the natives. Or, you can determine just what it is that's munching on your plant (collect a few if you don't know what they are and take them to your local nursery for positive identification) and use a chemical to control them.
Best wishes with your garden!
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