[Wikipedia] Oomycete Carrier: Adiantum jordanii is a carrier of the fungus-like oomycete, Phytophthora ramorum, which causes Sudden Oak Death. The USDA enforces an import control, focusing intensely on areas (CA, OR, NY in U.S.) that are infected with Sudden Oak death. When sold, they must be identified by place of origin and must also be accompanied by a phytosanitary certificate. The USDA warns to not take cuttings from wild specimens.[5] (link added by Mary Ann Machi)