This study examines the relation between folk expertise and wild plant classification in Little Dixie, a seven-county vernacular cultural region in central Missouri. A successive pile-sort task was administered to ten local wild plant "experts" and ten "novices" of Euro-American descent to investigate how ethnobotanical knowledge influences the cognitive construction of folk taxonomies. The results indicate that experts categorize plants according to utilitarian features (e.g., edibility, medicinal value) and morphology (e.g., herbs, trees) while novices rely almost exclusively on morphological traits. While the classification strategies of experts and novices are substantially different, a single categorization system is common to both groups. Novices vary less in their responses than experts, which is explained by the novices' use of a highly shared, imagistic classification system and the experts' mastery of alternate ways of categorizing the wild plant domain. These findings strongly suggest that ethnobotanical classification is based fundamentally on the recognition of ostensible perceptual features of plants, but progressively guided by the recognition of culturally learned functional attributes.