3Phylum Cycadophyta (cycads) Small (about 200 species)Mainly tropical1 U.S. species: found in Florida (Zamia pumila)
4Phylum Cycadophyta (cycads) Sporophyte features:Trunk woodyLeaves often spiny and pinnately compound (divided into thin sections: feather-like).NotewoodytrunkPinnately compoundleaf
5Phylum Cycadophyta (cycads) Sporophyte features:Pollen made in pollen conesEncephalartos pollen cones
6Phylum Cycadophyta (cycads) Sporophyte features:Seeds made in seed conesEncephalartos female coneMegasporophylls of CycasOvule-bearing leaf(megasporophyll) of cone
7Phylum Cycadophyta (cycads) Sporophyte features:Plants dioecious: separate male and female individuals.Cycas revoluta femaleCycas revoluta male
8Phylum Cycadophyta (cycads) Importance:Some used horticulturally: Cycas revoluta (sago palm)
9Phylum Cycadophyta (cycads) Importance:Some are endangered in the wildExample: South Africa has 40 species, all endangered
10Phylum Cycadophyta (cycads) Importance:Since 1965, must have permit to own cycad in South AfricaOne species extinct in wild. All plants left are males in gardens! Propagated by suckers (side branches).Encephalartos woodii, knownonly from male plants
11Phylum Cycadophyta (cycads) Importance:Was a dominant land plant group during dinosaur era (Mesozoic Era).
12Phylum Coniferophyta (conifers) Largest gymnosperm group: 600 speciesDominates biomes in far north and south temperate zonesMany species with narrow leaves (needle-leaved trees)Examples: Pines (Pinus), Junipers (Juniperus), Firs (Abies), Cypresses (Taxodium)
13Phylum Coniferophyta (conifers) Importance:Also dominant group during Mesozoic Era (dinosaur time!)
14Extinct Conifers Example, Petrified Forest National Park, Arizona Most trees there are extinct conifers whose trunks are mineralized.
15Phylum Coniferophyta (conifers) Importance:Conifer forest biome (covers large part of Earth’s landmass)Conifer forests occupy high mountains in North AmericaTemperate rain forest inWashington/Alaska
16Phylum Coniferophyta (conifers) Importance:Currently dominant in parts of North (and South) Temperate ZonesLight greenis taiga orboreal forest(conifers)
17Phylum Coniferophyta (conifers) Importance:Some communities in southeast dominated by conifersExample, cypress (Taxodium) swampsCypress branchCypress swamp near Monroeville AL
18Phylum Coniferophyta (conifers) Importance:Some communities in southeast dominated by conifersExample, cypress (Taxodium) swampsBIOL 6140 (Plant Ecology) classes explore swamps on field trips
19Phylum Coniferophyta (conifers) Importance:Biological records (largest tree)Sequoiadendron gigantea (big tree)In Sequoia National Park, CABase: 102 feet circumferenceWeight: 2,145 tonsVolume: 52,500 cubic feet.
21Phylum Coniferophyta (conifers) Importance:Biological records (oldest tree)Bristlecone Pine (Pinus longaeva). Found in high mountains of deserts of California, Nevada, Utah, Colorado, etc.
22Phylum Coniferophyta (conifers) Importance:Oldest tree was 4,950 years. Cut down in 1964 by graduate student who got corer stuck in tree (U.S. Forest Service gave permission!)Now oldest known bristlecone (named Methuselah) is 4,767 years old. Location kept secret from public!
23Phylum Coniferophyta (conifers) Importance:Biological records (tallest living tree)Coast redwood (Sequoia sempervirens)Grow on coast of California/Oregon (ex, Redwood National Park)96% have been logged
24Phylum Coniferophyta (conifers) Importance:Biological records (tallest living tree)Coast redwood (Sequoia sempervirens)Tallest tree is 368 feet tall!.
25Phylum Coniferophyta (conifers) Importance:Biological records (smallest trees?)Pygmy forest in Mendocino County, CA
26Phylum Coniferophyta (conifers) Importance:Biological records (smallest trees?)Pygmy forest in Mendocino County, CAHardpan (like cement) forms at about 1 foot depthDry in summer, floods in winter.
27Phylum Coniferophyta (conifers) Importance:Stress makes conifers (a pine and a cypress species) stuntedThe trees onthe right hadabout 30 rings(30 yr old!)
28Phylum Coniferophyta (conifers) Conifers in Southern Hemisphere tooExample, Wollemi “Pine” (Australia)Thought extinct, small stand found in in plants!DiscovererDavidNoble
29Conifers: Economic Importance Harvest for pulp and timberCan cause controversy, especially when old-growth and clearcuts involved.
30Conifers: Economic Importance Importance in Alabama: forestry #1 legal agricultural cropMany pine plantations in southeast.
31Conifers: Economic Importance Edible (pine “nuts” are pine seeds)Harvested from several species, including pinyon pine from western U.S. (shown below).PinyonpinePine seeds
32Conifers: Economic Importance Medicines: example, taxolAntitumor agent. First extracted from bark of Pacific Yew (Taxus) treeNow made synthetically.Pacific Yew, showingneedles and bark
33Phylum Coniferophyta (conifers) Importance:Threatened by humans (acid rain and forest decline)Acid rain areas (below) include some conifer forests.
34Phylum Coniferophyta (conifers) Importance:Acid rain and others stresses cause “forest decline”, weakness and death of conifer treesSeen in N. Europe and N. America.Damage/death of firtrees in Tennessee
35Phylum Ginkgophyta (Ginkgo) Tiny group (1 living species: Ginkgo biloba)Also called maidenhair tree
36Phylum Ginkgophyta (Ginkgo) Living fossil: Leaf fossils 150 million years oldPhoto of modern and fossil Gingko leaves
37Phylum Ginkgophyta (Ginkgo) May be oldest living species on Earth!Dinosaurs under a Ginkgo tree in the Mesozoic fall
38Phylum Ginkgophyta (Ginkgo) Today considered extinct in wildAncient trees (to 3,000 years old!) found in China & Japan, in temple gardens and places tended by people.Ancient temple tree in China
39Phylum Ginkgophyta (Ginkgo) Leaves winter deciduous, fan-shaped, with dichotomously-branching veinsMade on stubby “short shoots” on branchesShort shoots withleaf scars
40Phylum Ginkgophyta (Ginkgo) Gingko very useful horticultural treePollution resistant, makes beautiful street treeA very old bonsaiGinkgoGinkgo in fall on Japanese street
41Phylum Ginkgophyta (Gingko) A-bomb resistant!This tree in Hiroshima, Japan, was 1.1 km from where the first Atomic bomb was used in 1945.
42Phylum Ginkgophyta (Gingko) Medical uses:May improve circulation, memoryStill under studyPills of leaf extract worth millions of $/yr.Ginkgo farm (top) and drying leaves (bottom)
43Phylum Gnetophyta (gnetophytes) Small group (70 species)Only gymnosperms with vessels in xylem (large, dead water-conducting cells)
44Phylum Gnetophyta (gnetophytes) Three genera (2 mentioned here):Welwitschia from Namib desert (Africa)Odd, only 2 leaves!Old plant in Namib desertYoung plant grown in pipe section (long taproot)
45Phylum Gnetophyta (gnetophytes) Three genera (2 mentioned here):Ephedra from many deserts of worldShrub is mostly branches (ovules seen on right
46Phylum Gnetophyta (gnetophytes) Three genera (2 mentioned here):This shrub was original source of drug ephedrineUsed as stimulant, weight loss aid, may have side effects (stroke, etc.).You can buy ephedrine on the internetYou can also find lawyers to help yousue the makers of ephedrine pills!