Artificial Group Floriferae-Apetalae Subclass Hamamelidae Ulmaceae (Elm family) [Latin name] 18 Genera 150 species (5 on campus) I. Leaves A. Deciduous B. Alternate C. Simple D. Stipulate E. Pinnate venation F. Usually serrate/doubly serrate G. Usually inequilateral bases II. Flowers A. Perfect or imperfect (monoecious) B. 4-6 stamens C. 1 celled ovary with 1 ovule, 2 styles III. Fruit A. Samara, Drupe, Nut IV. Economic importance A. Ornamental shade trees B. Wood has superior strength, toughness and bending qualities -> containers that are exposed to rough handling V. Range A. Temperate regions of N. & S. hemispheres B. Few tropical species Generic Comparison I. Celtis (Hackberry) [Greek name] A. Serrate, often entire below middle B. Drupe C. 3 distinct veins at leaf base D. C. occidentalis (common hackberry [Western] II. Zellkova [common name in Caucasus] A. Serrate B. Drupe C. 7 or more pairs of pinnate veins D. Zelkova serrata (Japanese zelkova) III. Ulmus (Elms) A. Doubly serrate (most) B. Samara C. 7 or more pairs of pinnate veins Species Comparison I. U. americana (American Elm) A. Leaves smooth or slightly pubescent if rubbed from apex to base B. Brown to reddish brown twigs C. Brown buds D. Very susceptible to Dutch Elm Disease (1930) II. U. rubra (Red, Slippery Elm) A. Leaves rough with scabrous pubescence B. Gray pubescent twigs C. Black buds D. Brownish, furrowed bark III. U. glabra (Scotch, wych Elm) A. Leaves (8-16 cm) rough with scabrous pubescence, often with 2 small lobes B. Gray-brown pubescent twigs C. Black buds D. Gray, smooth bark E. Camperdown elm is cultivar with pendulous branches grafted on short trunk IV. U. parvifolia (Chinese Elm) [small flowered] A. Small leaves with single serrated margins and equilateral bases B. Puzzle shaped plates fall off to reveal orange inner bark on intermediate aged branches C. Flowers/Fruits in Fall Artificial Group Florifea Apetalae Subclass Hammamelidae Moraceae (Mullberry Family) [Latin name] 48 Genera 1,000 species (2 on campus) I. Leaves A. Alternate B. Simple C. Stipulate D. Latex II. Flowers A. Imperfect (monoecious or dioecious) B. 4 sepals, 4 stamens C. 2 -carpellate pistil III. Fruit A. Usually multiple fruit of drupes or achenes IV. Economic Importance A. Ornamental B. Edible fruit C. Asian silkworms feed on Morus leaves D. Latex for rubber from Ficus & Castilla V. Range A. Mostly tropical with a few temperate species Generic Comparison/Species Characteristics I. Morus (Mulberry) A. Smooth (glabrous or slightly pubescent) B. Lustrous C. Elliptical, Lobed, especially juvenile, or unlobed D. Serrate E. Bark with yellowish tinge F. M. alba (White Mulberry) Introduced from China in failed attempt to establish Silk industry G. M. alba var. Tatarica (Russian Mulberry) 1875 very hardy, red fruits II. Maclura (Osage orange, Hedge apple) Monotypic M. pomifera [apple bearing] A. Smooth B. Lustrous C. Oblong-lanceolate to ovate, Unlobed D. Entire E. Large spherical bright green multiple drupe F. Orange inner bark G. Yellow -> Orange wood from which yellow dye can be extracted with hot water Ornamentals within the Florifera Apetalae I. Eucommiaceae (Eucommia Family) A. Eucommia ulmoides (Hardy Rubber Tree) Monotypic genus native to China B. Latex like Morus C. Imperfect flowers like Ulmus, but is dioecious D. Samaras like Ulmus E. Dark green rugose leaves II. Cercidiphyllaceae (Katsura Tree Family) A. Cercidiphyllum japonicum Monotypic genus native of E. Asia B. Crenate margins C. Opposite -> Subopposite -> Alternate D. Dioecious