Achillea millefolium (Yarrow)
Acorus calamus (Sweet flag)
Agrimonia eupatorium (Agrimony)
Gentiana lutea (Gentian)
Harpagophytum procumbens (Devil's claw, Grapple plant)
Humulus lupulus (Hops)
Rheum officinalis (Rhubarb)
Silybum marianum (Milk thistle)
Taraxacum officinale (Dandelion, Lion's tooth)
Usnea spp. (Old man's beard)

References