3/8/2010. Taxus : The yews. Native to Maryland: Taxus canadensis (American Yew) Taxaceae. Low growing, spreading, evergreen shrub

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1 Taxaceae ~5 Genera species Trees and shrubs. Needles mostly alternate. Often spirally arranged but twisted so they appear two-ranked. Needles flattened and elongate, often linear. Needle bases extend down the stem. Two stomatal bands on lower surface. Male and female structures separate (plants mostly dioecious). Seeds borne singly; surrounded by fleshy, cup-like aril. Seeds mature in 1-2 seasons (1 for Taxus, 2 for Torreya). Angiosperm Phylogeny Webpage Taxus : The yews Considered to be premier needle-leaf evergreens for landscape use Mostly trees in the wild, mostly shrubs in landscaping Native to Maryland: Taxus canadensis (American Yew) Low growing, spreading, evergreen shrub Hans-Otto Tengrud In rich moist woods, Garrett County University of Connecticut G. Timmermans J. Johnson 1

2 Taxus : The yews The source of Taxol (paclitexel) an anti-tumor compound. Used to treat breast cancer, ovarian cancer, and certain types of lung cancer. Found in Taxus brevifolia (Pacific yew) in1962, published in 1971, clinical trials were finished in Treating one cancer patient with Taxol requires 60 pounds of Yew tree bark equivalent of three, one hundred year old trees Related compounds (including docetaxel) found in 14 yew species. Sciadopityaceae 1 Genus 1 species Sciadopitys verticillata Evergreen tree. Two types of leaves : Scale leaves arranged spirally along the stems. Needles in whorls at the nodes. Flattened, with deep furrow at midrib on top and bottom. Monoecious. Female cones with bracts enclosed by cone scales. Seeds 5-9 per scale. Cones at branch tips. rboretum de Villardebelle Ar CJ Earle University of Connecticut Dave Powell University of Connecticut Araucariaceae 3 Genera 40 species Evergreen trees. Native to the southern hemisphere, mostly in the tropical rainforest. Leaves narrow or broad, spirally arranged. Leaves often with parallel veins. Dioecious or monoecious. Male cones relatively large, cylindrical, with numerous spore bearing bracts Female cone usually borne erect subglobose to ovoid, maturing in two years relatively large and milky falling upon maturity scales one-seeded without distinct bracts Araucaria heterophylla Norfolk Island pine 2

3 Araucaria araucana Monkey puzzle tree Podocarpaceae 18 Genera 173 species Evergreen trees and some shrubs. Native to the southern and northern hemispheres. Leaves alternate or opposite; scale like, needle-like, or broad and flat. Dioecious or monoecious. Male cones catkin like. Female cone pendant, much reduced to a few fleshy bracts, maturing in one year. Seeds covered by a fleshy coat. Podocarpaceae 18 Genera 173 species Evergreen Trees and some shrubs Native to the southern and northern hemispheres Leaves alternate or opposite; scale like, needle-like, or broad and flat Dioecious or monoecious Male cones catkin like Female cone pendant, much reduced to a few fleshy bracts, maturing in one year Seeds covered by a fleshy coat Podocarpus macrophyllus Southern yew Yew podocarp Buddhist pine Anonymous 3

4 Figure 7.15 Alternative hypotheses of relationships among the 5 major extant lineages of seed plants Angiosperm Phylogeny Webpage Angiosperms Have flowers Seeds produced in protected ovaries Most have vessels for conducting water ~250, ,000 species Earliest fossils are from the Cretaceous (~135 mya) Compare to 425 mya for earliest land plants By 100 mya, angiosperms dominate Primitive Traits in Angiosperms Vegetation Perennial Woody Evergreen Flowers Radially symmetrical. Parts several to numerous. Parts spirally arranged. Petals and sepals not differentiated (tepals). Stamens poorly differentiated into anthers and filaments. Dennis Stevenson Gynoecium superior. Carpel with elongate stigma and style that are poorly differentiated. Ovaries sealed by a secretion. Ovules attached to the locule walls. Sangtae Kim 4

5 Figure 7.16 Phylogenetic relationships at base of angiosperms Sangtae Kim Amborellaceae 1 genus, 1 species Amborella trichopoda Sprawling shrubs to small trees. Leaves simple, alternate; t spiral, to distichous. Lacking stipules. Wavy or rippled margins. Leaf blade pinnately dissected to entire. Stan Shebs 5

6 Amborellaceae Nymphaeaceae Colby College FloralImages.com 1 genus, 1 species 5 genera, 70 species Amborella trichopoda Flowers unisexual, plants dioecious. Petals and sepals undifferentiated (tepals), spirally arranged. Indeterminate number: 5-8 in female, 9-11 in male. Stamens , leaf-like. Gynoecium superior. 5 8 carpelled; apocarpous. Carpels not completely ltl closed (unsealed at the tip). Stigma sessile with two expanded flanges. 1 ovuled per carpel Placentation marginal. Scott Zona Magnus Manske Aquatic, rhizomatous herbs. Leaves peltate; alternate and spirally arranged Long-peduncled bisexual flowers with numerous parts. Fruit a berry, indehiscent pod, or a capsule; a schizocarp. Victoria amazonica Important genera Nuphar Nymphaea Sangtae Kim Sangtae Kim bidorbuy.com Austrobaileyales 3-4 Families Austrobaileyaceae Schisandraceae Illiciaceae Trimeniaceae Arria Belli Austrobaileya scandens Ilicium henryi Scott Zona Ilicium religiosum Schisandra rubriflora Scott Zona Austrobaileyales In United States Schisandra glabra baystar vine Illiciaceae Illicium floridanum Florida anise, star anise Schisandraceae Matt Valente Scott Zona Schisandra glabra Dennis Stevenson Matt Valente Alabama Plants 6

7 Magnoliaceae 2 genera, 227 species -Trees and shrubs. -Simple leaves. -Stipules present -Entire or lobed leaf blades. -Large solitary flowers, leaving large scars. -Flowers -radially symmetrical. -with an elongated receptacle bearing many separate petals, stamens and pistils. -Fruits are aggregates of follicles or aggregates of samaras. 7

8 Magnolia virginiana Sweetbay Magnoliaceae -Large stipules that entirely surround the stem are open on the side opposite the petiole. -Leave a distinctive ring around the stem. Magnolia virginiana Sweetbay Magnoliaceae 8

9 Magnolia grandiflora Southern magnolia Magnoliaceae Liriodendron tulipifera tulip tree Magnoliaceae Thick, leathery, evergreen leaves. Leaves shiny on top and brown scurfy on the bottom. Flowers HUGE, white. 9

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