The original species from Europe Agrimonia eupatoria is edible with the leaves and flowers used as a tea or to flavor alcoholic beverages. Medicinally its leaves and seeds are astringent, anti-inflammatory, and anti-bacterial, the leaves can be placed under your pillow to induce sleep or act as a topical treatment for migraines.
No idea what traits the "swamp" variety retained though.
Snakes? You mean danger noodles?
Onion rings are vegetable donuts. Taste this tiny ad:
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