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Combine the following ingredients in a pan to create a nutritious formula for the butterflies: Paint mixture on trees, stumps, rocks, or tree posts.
3 mashed, overripe bananas 1 or 2 cans of stale beer 1 pound white sugar 1 cup maple syrup 1 cup fruit juice 1 shot of rum Alternatively, you may soak a sponge in the liquid and hang it from a tree limb.