Ptelea trifoliata (wafer ash) is a wonderful much under-utilized native shrub that doubles as a host plant for several butterflies including Papilio cresphontes (giant swallowtail). Thrives in a wide range of conditions including hot/dry slopes to woodland edges to any garden bed. Copious yellow flowers in the spring are followed by persistent seed disks. Disease-free and drought tolerant. In the citrus family.