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Useful Field Characteristics for Representative Families

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Useful Field Characteristics for Representative Families Useful Field Characteristics for Representative Families Liliaceae • usually herbs, often scapose • monoecious • stems often modified as rhizomes, bulbs • staminate spikes above pistillate spikes or corms • perianth of bristles • flowers actinomorphic • perianth usually undifferentiated Juncaceae • 6 tepals (or 3 sepals and 3 petals), 6 • herbs with round, usually solid stems stamens, 3 carpels • leaves basal, 3-ranked, with open or • ovary superior (or inferior) closed sheaths • capsule or berry • flowers usually bisexual • tepals 6 Iridaceae • stamens 3 or 6 • herbs • carpels 3, connate; capsule • leaves 2-ranked and equitant • flowers actinomorphic or zygomorphic Cyperaceae • perianth undifferentiated or differentiated • herbs • 6 tepals (or 3 sepals and 3 petals), 3 • stems typically triangular, sometimes stamens, 3 carpels round • styles sometimes winged and petaloid • leaves basal or cauline, 3-ranked, with • ovary inferior closed sheaths • capsule • inflorescence a spikelet, subtended by 1 bract Orchidaceae • flowers unisexual or bisexual • terrestrial or epiphytic herbs with • each flower subtended by 1 bract pseudobulbs • perianth of bristles or absent • flowers zygomorphic • achene • 3 sepals, 3 petals, 1-2 stamens, 3 carpels Poaceae / Gramineae • labellum, column, pollinia • herbs with round, usually hollow stems • ovary inferior • leaves basal or cauline, 2-ranked, • capsule usually with open sheaths • ligule between leaf sheath and leaf blade Araceae • inflorescence a spikelet with 1 to many • mostly terrestrial herbs florets • watery or milky sap • each spikelet subtended by 2 bracts • calcium oxalate crystals (glumes) • leaves often not parallel-veined • flowers unisexual or bisexual • spathe and spadix • each floret subtended by 2 bracts – • flowers often with fetid odor lemma and palea • perianth of lodicules Bromeliaceae • caryopsis (grain) • mostly tropical herbs, often epiphytic • water absorbing peltate scales Arecaceae / Palmae • leaves alternate often forming water • trees or shrubs with unbranched stems 'tanks' • leaves crowded at stem tip to form • flowers actinomorphic, bisexual crown, pinnately or palmately compound • flower parts in 3's • flowers actinomorphic, bisexual or • ovary superior to inferior unisexual, 3-parted • capsule or berry • drupe Typhaceae Magnoliaceae • herbs • trees & shrubs • leaves basal and sword-shaped • flowers large and showy • floral parts numerous, separate, spirally separate catkins arranged • seeds numerous and comose (hairy) • many tepals • elongate receptacle Crassulaceae • laminar stamens • succulent herbs • leaves succulent Ranunculaceae • flowers actinomorphic, bisexual • usually herbs • carpels 4 or 5 distinct; ovaries superior • leaves simple and deeply lobed or • fruit an aggregate of follicles compound • stamens usually many Caryophyllaceae • 1-many pistils • herbs • leaves simple, opposite Papaveraceae • swollen nodes • herbs with milky sap (can be colored) • petals entire to deeply lobed, often • leaves simple often lobed or dissected differentiated into a claw and a limb • flowers actinomorphic (Papaveroideae) • floral parts in 5's or zygomorphic (Fumarioideae) • placentation often freecentral • 2 deciduous sepals, 4 petals often wrinkled Cactaceae • Stamens numerous (Papaveroideae) OR • stem succulents 6 and diadelphous (Fumarioideae) • areoles with spines & glochids • Fruit a capsule • flowers showy, many tepals • floral parts numerous, spirally arranged Nymphaeaceae • ovary inferior • aquatic herbs • placentation usually parietal • leaves with blade submerged, floating, or emergent Portulacaceae • flowers with long pedicel, floating or • usually herbs raised above water • 2 (to several) sepals • tepals many, stamens numerous • plants often fleshy • leaves simple, opposite or alternate Betulaceae • basal placentation • trees or shrubs • leaves simple, alternate, and doubly Polygonaceae serrate • leaves alternate, with sheathing stipules • monoecious plants (ocreas), except Eriogonum with whorled • pistillate and staminate flowers in or opposite leaves and no ocrea separate catkins • one floral envelope, 6 persistent tepals • each flower subtended by 1-2 bracts • 6-9 stamens • ovary inferior (2 fused carpels) • achene, often winged • nut, samara Aceraceae Fagaceae • trees or shrubs • trees or shrubs • leaves simple, opposite, often palmately • leaves simple, alternate lobed • monoecious plants • nectary disk • 1-3 pistillate flowers in leaf axils • carpels 2, connate • staminate flowers in catkins • ovary superior • ovary inferior (3 fused carpels) • samaroid schizocarp • nut with involucre of bracts Brassicaceae / Cruciferae Salicaceae • herbs • trees or shrubs • mustard oils • dioecious plants • 4 sepals, 4 petals, 4 + 2 stamens • pistillate and staminate flowers in (tetradynamous) • 2 fused carpels • silicle or silique Rosaceae • trees, shrubs, or herbs Malvaceae • leaves simple or compound; stipulate • usually herbs or shrubs • leaflets with serrate margins • leaves simple, commonly palmately • hypanthium lobed • pistils numerous to 1 • stellate hairs • ovary inferior to superior • bracteolate calyx • variation in fruit types • stamens monadelphous, or in 5 clusters, each with filaments basally connate Fabaceae / Leguminosae • capsules (often schizocarpous) • trees, shrubs or herbs • leaves often compound; stipulate Onagraceae • leaflets with entire margins • usually herbs • stamens numerous to 10, diadelphous in • 4 sepals, 4 petals, 8 stamens, 4 carpels papilionaceous flowers • petals often clawed or stipitate • carpel 1 (per flower) • hypanthium present • legume or loment • ovary inferior • usually capsule Ericaceae • trees & shrubs Geraniaceae • leaves opposite or alternate, entire • herbs • corolla usually sympetalous, frequently • leaves usually palmate, simple to urceolate & pendulous compound • 10 stamens (rarely 5) • flowers actinomorphic, parts in 5's • anthers usually with poricidal dehiscence • elongate stylar, sterile column and often with appendages • ovary superior, elongating after • 3-5 fused carpels; style 1 +/- capitate pollinatioin • schizocarp of 5 segments; 5 fused Polemoniaceae carpels • usually herbs • flowers actinomorphic Violaceae • corolla sympetalous, convolute in bud • usually herbs • unequal insertion of stamens on corolla • flowers zygomorphic • carpels 3, connate • corolla polypetalous, spurred • stigmas separate (3) • nectar guides • ovary superior • stamens connivent Cornaceae Saxifragaceae • trees or shrubs • usually herbs • leaves simple, opposite, veins arcing • leaves often basal, often serrate and from base to tip palmately lobed • “dogwood test” • hypanthium present • inflorescence often subtended by showy • carpels usually 2-3 (6), partially fused bracts • styles separate • flowers actinomorphic, bisexual or unisexual Euphorbiaceae • flower parts usually in 4's (4 sepals, 4 • herbs or shrubs petals, 4 stamens) • milky latex • ovary inferior • reduced flowers, unisexual • drupe • inflorescence often highly modified into a false flower Boraginaceae • carpels 3, connate • herbs • schizocarpous capsule, forming 3 one- • plants often hairy seeded parts • leaves alternate • scorpioid or helicoid cymes Scrophulariaceae s.l. • flowers actinomorphic • usually herbs • corolla sympetalous • flowers zygomorphic • style gynobasic OR terminal and bifid • corolla sympetalous, bilabiate • if style terminal and bifid, then stamens • didynamous fertile stamens (or 2) usually exserted • ovary superior; carpels 2, fused; ovules • ovary superior, 4-lobed (when numerous gynobasic) OR unilocular • capsule or berry • 4 nutlets (when gynobasic) OR capsule Apiaceae / Umbelliferae Solanaceae • mostly perennial herbs with hollow stems • usually herbs, shrubs, or vines • leaves compound, dissected, with • plants often densely pubescent sheathing base • leaves simple, alternate, commonly • umbels, often subtended by involucre of lobed bracts • flowers actinomorphic, sympetalous • carpels 2, connate • connivent anthers in Solanum • ovary inferior • 2 fused carpels, capitate stigma • schizocarp • ovary superior Caprifoliaceae Rubiaceae • mostly woody • trees, shrubs, vines, herbs • leaves opposite, simple • leaves opposite or whorled, entire • flowers zygomorphic • stipules present, interpetiolar and usually • petals 5, connate with long tube: 2 upper connate and 3 lower lobes, or 4 upper and 1 • flowers actinomorphic, 4- or 5-parted lower lobe; sometimes spurred • stamens 4 or 5 • 2-5 fused carpels • carpels 2, connate • ovary inferior; style elongate, stigma • ovary inferior capitate • nectar producing glandular hairs on inner Apocynaceae surface of corolla tube • trees, shrubs, vines, herbs • berry, capsule, or drupe • milky latex • leaves opposite or whorled Asteraceae / Compositae • flowers actinomorphic • head or capitulum, surrounded by • gynostegium, pollinia, corona phyllaries (Asclepiadaceae) • disk or disk and ray or ligulate flowers • ovary superior; 2 carpels united at styles • pappus or none only • corolla sympetalous • top of style expanded and highly • anthers connate modified • ovary inferior • paired follicles • achene (cypsela) Lamiaceae / Labiatae Campanulaceae • aromatic herbs • herbs with milky sap • square stems • leaves alternate • leaves opposite and decussate or • flowers actinomorphic or zygomorphic whorled • petals 5, connate • flowers zygomorphic • corolla bell-shaped (tubular) OR 2-lipped • corolla sympetalous, bilabiate and then with dorsal slit • didynamous stamens (or 2) • stamens 5, attached to disk at top of • gynobasic style (usually) ovary • ovary superior; carpels 2, fused; 2 • anthers connate ovules/carpel • carpels 2-5, connate, ovary inferior to 1/2 • 4 nutlets (usually) inferior • capsule or berry .
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