Celtis
Celtis aetnensis, Celtis australis, Celtis laevigata, Celtis laevigata (Sugarberry), Celtis occidentalis, Celtis reticulata, Celtis sinensis
Ulmus
Ulmus americana, About Elm Trees, The Return of the Elm, Ulmus canescens, Ulmus procera, Ulmus rubra
Families of Flowering Plants: Ulmaceae
Description of this family of trees and shrubs, including anatomy and morphology, physiology and biochemistry, geography, and economic uses.
Ulmaceae - The Elm Family
Brief illustrated description of this family of woody plants, mostly trees, found primarily in northern, temperate regions.