1. Ground pine thickly covered with bristly leaves; widely distributed in barren sandy or peaty moist coastal regions of eastern and southeastern United States
   - foxtail grass

Type of: Christmas green, ground pine

• genus Xanthomonas
• genus Xanthorroea
• genus Xanthosoma
• genus Xenicus
• genus Xenopus
• genus Xenorhyncus
• genus Xenosaurus
• genus Xeranthemum
• genus Xerobates
• genus Xerophyllum
• genus Xiphias
• genus Xylaria
• genus Xylocopa
• genus Xylomelum
• genus Xylopia
• genus Xylosma
• genus Xyphophorus
• genus Xyris
• genus Yucca
• genus Zaglossus
• genus Zalophus
• genus Zamia
• genus Zannichellia
• genus Zantedeschia
• genus Zanthoxylum