citrus family spice or flavor-producing plant prickly ash plant WIKIPEDIA:Zanthoxylum Zanthoxylum (including Fagara) is a genus of about 250 species of deciduous and evergreen trees and shrubs in the citrus or rue family, Rutaceae, native to warm temperate and subtropical areas worldwide. Common names include Prickly-ash and Hercules' Club. zanthoxylum spp. requires discussion