Diversity and Evolutionof Rosids. . . gourds, oaks, and violets . . .Cucurbitales• previously recognized group of 7families (some N2 fixers)• palmate leaves, cucurbitoid teeth,imperfect flowers, parietalplacentationDatiscaceaeCucurbitaceaeBegoniaceaeN2 fixingcladeMainly tropical and subtropical family of 118 genera,845 species of herbaceous or woody vines with tendrils(modified inflorescences)Gurania in Panama Cucumis in WisconsinCucurbitaceae - melons• flowers unisexual andplants usually dioecious,cultivated ones monoeciousMale flower Female flower• fusion of perianth (Asterid-like!); stamens are weird,female flower is epigynousCucurbitaceae - melonsFruit is a berry with leatheryrind = *pepo (pumpkin,melon, pickle, gourd)Female flowerCucurbitaceae - melonsEchinocystis lobata wild cucumberNote the many small maleflowers and few femaleflowers going into fruit andspiny pepoCucurbitaceae - melonsSicyos angulata - bur cucumberSmall “burred” cucumberor pickle-like fruits can beseen on bottom rightCucurbitaceae - melons*Fagales• core “Amentiferae” of Engler &Prantl and subclass “Hamamelidae”of Cronquist - wind pollinatedN2 fixingclade• trees with unisexualflowers in aments/catkins• inferior G (2-3)• nut - bony 1-seeded*FagalesNothofagaceae - southern beeches -are sister to all others• North Temperate family of 7 genera, 670 species (1/2 are oaks)Castanea - chestnut Quercus - oak*Fagaceae - beechesFagus - beech• simple leaves and nut enclosed by subtending bracts• Fagus (beech) is characteristic of mesic forests in northtemperate deciduous forests• easy to recognize with gray barkFagus grandifolia -American beech• 2 pistillate flowers (2 nuts)surrounded by one set of bractsFagus sylvatica - EuropeFagus grandifolia - N. America*Fagaceae - beeches• Quercus, the oaks, have bracts belowfemale flower that coalesce into awoody cup of the acorn fruit (nut)• hybridizing group and taxonomicallychallenging*Fagaceae - oaks• White oaks - rounded leaf lobes,thinner walled xylem of summer wood,fruit matures in 1 yr• Red oaks - bristle tipped leaf lobes,thicker xylem, fruit matures in 2 yrs*Fagaceae - oakswhite oak red oakQuercus alba - white oakWhite oak - Alleghenian species typicalof more mesic woodlands in Wisconsin*Fagaceae - oaksBur oak - Ozarkian element species ofxeric oak woodlands and oak savannasQuercus macrocarpa - bur oak*Fagaceae - oaksRed oak - more mesic member of the redoak group; black oak, hill’s oak are morexeric tolerantQuercus rubra - red oak*Fagaceae - oaks• Castanea, the chestnuts, have 2female flowers per spiny involucreCastanea dentata - American chestnut*Fagaceae - chestnutsCastanea dentata - Americanchestnut original distributionAmerican chestnutsMassachusetts in late1800s prior to 1904chestnut blightJapanese chestnut inConnecticut -resistant*Fagaceae - chestnutsWell known tree family containing walnuts, hickories, andpecans10 genera and 50 species are divided into two subfamilies*Juglandaceae - walnutsEngelhardia Juglans• Leaves pinnately compound,alternate• Leaves often aromatic from resinouspeltate glands; allelopathicJuglans cineraButternut, white walnutCarya ovatashagbark hickory*Juglandaceae - walnuts• Trees aremonoecious• Wind pollinatedfeaturesJuglans nigra - Black walnutFemale flowerMale inflorescence*Juglandaceae - walnuts• male flowers apetalous andarranged in pendulous catkins oraments on older stems• calyx small; each flower bractedCA 3-6 CO 0 A 3-∞ G 0Juglans regiaEnglish walnut*Juglandaceae - walnutsJuglans cineraButternut, white walnutCA 4 CO 0 A 0 G (2)• female flowers apetalous and in asmall group on this year’s new growth• calyx small, persistant, often fused toinvolucral bracts; 2 stigma featheryJuglans cineraButternut, white walnutJuglans nigraBlack walnut*Juglandaceae - walnutsCarya cordiformis Bitternut hickoryJuglans cineraButternut, white walnut• fruit a nut - single ovule fused to ovary wall• surrounded often by persistant involucral bracts which canbecome fleshy; thus sometimes mistakenly called a “drupe”Juglans nigraBlack walnut*Juglandaceae - walnutsJuglans nigra - black walnut• black walnut: one of the mostprized of all lumber trees for finefurniture*Juglandaceae - walnuts• shagbark hickory: common tree ofmore mesic to xeric forests over muchof North America - oak/hickory forestsCarya ovata - shagbark hickory*Juglandaceae - hickories*Betulaceae - birchesNorth Temperate family of 6 genera and110 species of shrubs to trees - birchesand alders• both female and male (drooping)inflorescences are in aments/catkins• flowers possess no perianth• fruit a small nut or 1 seeded samara,subtended by 3-lobed bract*Betulaceae - birchesBetula papyrifera - paper birchFemale inflorescenceMale inflorescence*Betulaceae - birchesBetula papyrifera -paper birchBetula allegheniensisyellow birch*Betulaceae - birchesOstrya virginiana - easternhop hornbeam, ironwoodAlnus, the aldersCorylus americanaHazelnut, filbertMyrica gale - sweet gale Comptonia peregrina - sweet fern• Small family 3 genera that fixatmospheric nitrogen• Dioecious shrubs or subshrubswith sweet aromatic smellMyricaceae - sweet galeCasuarina -evergreen withequisetoid leavesCasuarinaceae• small family of 100 species -the she oaks of AustraliaOxalidales• small, heterogeneous, novel groupof 6 families - seed character?CephalotaceaeAustralian pitcher plantOxalidaceaeWood sorrels6 genera, 770 species in the tropics and temperate areas - 700belong to Oxalis (wood sorrel)Oxalidaceae - wood sorrels• plants are herbaceous creepers or woodyvinesOxalidaceae - wood sorrelsOxalis corniculata - creeping yellow wood sorrel• typically 3-foliateleaves (the realshamrock)• leaves are acidic totaste due to oxalicacid in the form ofcalcium oxalate6 genera, 770 species in the tropics and temperate areas - 700belong to Oxalis (wood sorrel)Oxalidaceae - wood sorrelsOxalis corniculata • 5 merous flowers• fruits are 5 locular &winged capsules or berriesCA 5 CO 5 A 5+5 G (5)OxalisOxalidaceae - wood sorrelsOxalis corniculata • 5 merous flowers• fruits are 5 locular &winged capsules or berries• tristyly common (3 levelsat which 2 sets of anthersand 1 set of styles position)CA 5 CO 5 A 5+5 G (5)OxalisU U UOxalis stricta -tall wood-sorrelOxalidaceae - wood sorrelsOxalis acetosella -wood-sorrelOxalis violaceae -violet wood-sorrel• common native and introduced wood-sorrelsOxalidaceae - wood
View Full Document