Thompson’s yucca grows 6-12 feet high, treelike, with a trunk 5-8 inches in diameter. The trunk is usually unbranched. The leaves are narrow and stiff and grow in a radiating mass near the top; they are 8-24 inches long and about 1/2 inch wide in the middle. They gradually widen from the base to the middle, then narrow to a needlelike spine at the tip. The margins are horny, pale yellow, and more or less fine-toothed. The stout, 2-3 ft. flowering stalk holds a dense panicle of white flowers slightly above the foliage.Beaked yucca, Yucca thompsoniana (formerly Y. rostrata), gets its common name from the shape of its fruit. It. Many yuccas get unkempt, with shaggy, brown leaves hanging down; Thompson Yucca stays neat. It will adapt to any soil and reflected heat.