Jo trees were plants native to Cularin. Florists in local areas such as Gadrin often used jo cuttings in their arrangements. Caarites had a reaction to jo trees, becoming uncomfortable in proximity to jo cuttings. Some Caarites, such as Jyll Xon, had more severe allergic reactions, passing out and going into convulsions if they sniffed an arrangement containing jo clippings. Fortunately, these reactions were not life threatening.