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I. Classification of Angiosperms
The classification of angiosperms has been unclear for some time. However, with recent DNA sequencing studies, the relationships of flowering plants are now being uncovered and a new (APG - Angiosperm Phylogeny Group) classification system has been recently published. Many books (including most manuals and floras) use older classification systems, especially that of Arthur Cronquist from the New York Botanical Garden. Traditionally the flowering plants are called Magnoliophyta and were used to be divided into two classes - dicots (Magnoliopsida) and monocots (Liliopsida)
II. Order Magnoliales
Magnoliaceae - magnolia family
Not found in Wisconsin but part of the Alleghenian flora. Tropical trees with ethereal oils which leads to a strong scent. They typically have simple, alternate entire leaves.
Magnolia grandifolia -magonlia
This species is native to SE U.S. but is widely
cultivated due to its large flowers.
Primitive family: Long axis with elongate receptacle, many free
part arranged spirally; Stamens laminar, short and thick and
not differentiated into filament and anther; Gynoecium of many
separate (apocarpic) pistils or carpels.
CAµ COµ Aµ Gµ
Typically pollinated by beetles, which may
be trapped in the flower for a long period of time and often
eat the pollen and/or various flower tissues
Fruit a follicle and aggregate of them; follicle: a dry
dehiscent fruit derive from one carpel and opens along one side.
Liriodendron tulipfera - tulip tree
An important timber tree of the Alleghenian element getting into the Great Lakes region, but does not extend into Wisconsin.
II. Order Aristolochiales
Aristolochiaceae - dutchman's pipe or birthwort family
8-10 genera and about 600 species worldwide; 1 species in Wisconsin. Mostly vines in the tropical regions, but herbs in temperate. The family occurs mostly in tropical forests and warm temperate scrub forests. One species in Europe, Artistolochia clematis, was thought to resemble the curved position of human fetuses, giving rise to the notion that various concoctions of these plants ought to be good for pregnancy and childbirth [birthwort, "well born", aristocrat for family name], and it turns out that the plants actually produce a compoud that stimulates abortion.
Asarum canadense - wild ginger CA3 CO3 A12 G[6] capsule;
Creeping rhizome; pair of cordate (heart-shaped) per year; hairy plants with trichomes over the petioles, flower etc. Red/brown flowers arise between the leaves; foetid smell suggests that it is fly or beetle pollinated. Inferior ovary with 3 sepals and the stamens arising from top; the petals are absent. Seeds are dispersed by ants; these seeds possess an aril-like structure.
Used by eastern native Americans as a contraceptive, thick rhizome root can be cut up, boiled, and cooked in heavy sugar syrup to make candied ginger.
III. Order Nymphaeales
Nymphaeaceae - water lily family [now includes the family Cabombaceae]
Now shown to be almost the first flowering plants that split off after the rise of angiosperms - only one monotypic family in New Caledonia is more basal. These are aquatic herbs and thus unlike most orders of angiosperms, the Nymphaeales have an obvious ecological niche, they inhabit still waters and many of their characteristics reflect adaptations to this habitat.
floating leaves with long petioles
air cavities in petioles, peduncles,
lack of vessel elements
They are not related to other aquatic families often considered in the same order - Nelumbonaceae, Ceratophyllaceae.
Nymphaea - water lily; 2 species in WI, the flower are typically white with conspicuous petals; sepals are green; these showy flowers often attract various insects as pollinators: beetles, flies, bees
Nuphar variegata - yellow pond lily or the bull-head pond lily; the flowers are typically yellow, the sepals look petal like and the pet are inconspicuous; CA 3+3 CO 22 A G F leathery berry
Brasenia shreberi - water shield; wind pollinated floating leaved aquatic[formerly Cabombaceae]
Cabomba - fanwort, cabomba); submersed or floating leaved aquatic, insect pollinated [formerly Cabombaceae]
IV. Order Ranunculales
Ranunculaceae - buttercup or crowfoot family
60 genera, about 2500 species worldwide; distribution worldwide but is centered in temperate and cold regions of the northern and southern hemispheres. 13 native genera, 53 species in WI, 20 of these in Ranunculus , 1 species naturalized.
Herbs, sometimes woody or herbaceous climbers or low shrubs. Leaves, alternate sheathing, usually basal and cauline, often divided or compound, or palmately lobed.· No stipules. Flowers very variable: except many stamens and many free carpels (apocarpic). Floral shape varies: some actinomorphic/zygomorphic and some have spurs. Mostly insect and animal pollinated group. Mostly bisexual flowers, but some species dioecious.
CA 3+ CO (0)5+ A µ G3+
Fruits vary: follicles, achenes, berries
Aconitum noveboracense - monk's hood; petaloid sepals of which th upper forms a conspicuous hood; highly poisonous, Victorian medical books give lurid details of the symptoms and deaths of gardeners who have indverently eaten the roots of other species, mistaking them for Jeruselum artichokes.
Anemonella thalictroides - rue anemone; whorl of involucral leaves below umbel and + basal leaves; leaves usually three parted; typically found in open woods throughout the state `Aggregate of achenes Achene: one seeded fruit that does not open, but the seed is free from the pericarp - e.g. Anemone & Ranunculus
Anemone patens - American pasque flower, prairie smoke; on original prairies only; mostly in the south part of the state; no petals present, only sepals plus bracts below flower
Aquilegia canadensis - columbine; generally associated with deciduous or mixed woods, but usually at borders or clearings, river banks, roadsidse. Flower is pollinated by hummingbirds as one would expect from a red flower with long nectar-filled spurs; fruits follicles.
Caltha paulstris - marsh marigold or cowslip. A familiar plant to most people, sometimes carpeting wet places with brilliant yellow flowers in early spring. Flowers have no petals, perianth more or less petaloid sepals. Follicle: fruit from a single carpel, dehiscing (opening) along a single suture.
Hepatica americana (now placed in Anemone) - round lobed hepatica. Very distinctive 3 lobed leaves - doctrine of signatures suggests the plant is medicinally important for liver treatments; often found in beech-maple forests `flower one of the first, and therefore most welcome, plants to bloom in spring at which time the leaves are very small, pilose,and undeveloped.
Ranunculus abortivus - small-flowered buttercup. The largest genus in the family here in WI; achenes.
Ranunculus fascicularis - early buttercup or early crowfoot. Common in dry hillsides and sandy oak woodlands; another early spring bloomer.
Thalictrum dioicum - early meadow rue. Unlike most of the family, these are wind pollinated and have male and female flowers on separate plants (dioecious).
Berberidaceae - barberry family
13 genera, 660 species; widespread in temperate regions of Northern hemisphere. 3 native genera to Wisconsin + Berberis which is cultivated here. Many prized cultivated plants.
Small shrubs (Berberis) or herbs (rest of family). Leaves alternate or opposite (Podophyllum). 1 pistil of 1 carpel: hypogynous with marginal placentation. 3 or 4 merous. Anthers open by valves that lift up from the base or longitudinal slits in Podophyllum. Unusual disjunct biegeographic affinities with East Asia and East U.S. disjuncts.
Berberis vulgaris, the commone barberry, is the alternate host of the stem rust of wheat.
Podophyllum peltatum - may apple; CA 3+3 CO 3+3 A 12-18 G 1 F berry
Another familiar herb; forming large colonies of deeply lobed, peltate leaves whose umbrella like aspect is emphasized as they emerge from the ground, slits in anthers, sepals caducous, eastern North America with 10 other species in Asia and Himalayas - Arcto-tertiary relic distribution. Sometimes incorrectely referred to as mandrake; in another species, P. hexandrum, the rhizomes have a resin drastic purgatic and emetic properties which are incorporated into certain types of commercial laxatives.Caulophyllum thalictroides - blue cohosh; CA 6 CO 6 A 6 G1
Leaves thrice compound; the foliage resembles Thalictrum, hence the specific epithet. Petals with conspicuous bracts and nectaries; lids in anthers. Developing ovules break ovary wall so it is a naked seed with fleshy blue seed coat; in fact the fruit is more attractive than the flower and often remains on the plant for a long while. Medicinally important for North American native Americans.Jeffersonia diphylla - twin leaf; 4 merous CA 4 CO 8 A 8 G1
Attractive, unusual plant; rare and found in southern WI
Papaveraceae - poppy family
25 genera and about 200 species. In Wisconsin there are 5 genera and 6 species; about 3 of these are introduced and rarely escaped. This family is important to families for many reasons, from floral beauty to hard drugs - Papaver - is the source of opium and its derivatives, but most species have some interesting compounds.
Mainly herbaceous annuals, some herbaceous perennials or shrubs. Leaves alternate, without stipules. Many produce latex: often colored orange red, Native Americans used for war paint. Flowers large and conspicuous, and sepals caducous fall off early.
Sanquinaria canadensis - bloodroot
Monotypic genus; petals 8-12 with many stamens, red-orange sap abundant. Found in rich woods throughout the state; fruit a many seeded capsule.Chelidonium - celandine. Uncommon weed naturalized from Europe; unlike bloodroot the petals are not crumpled in bud
Fumariaceae - fumitory family
19 genera and 400 species worldwide occurring mainly in North temperate regions, but also in South Africa. In Wisconsin there are 4 genera, 7 species; these being spring ephemerals. Sometimes treated as part of the Papaveraceae - thus, considered to be a zygomorphic poppy.
Annual or perennial herbs; herbs with watery juices. Leaves alternate without stipules, sometimes pinnately or palmately compound. Zygomorphic or bilateral symmetry : 2 sepals, 4 petals modificed into sacs or spurs; stamens united into 2 groups: diadelphous.
Dicentra cucullaria - Dutchman's breeches; Dicentra canadensis - squirrel corn. Two familiar wildflowers with orange/red or yellow bulblets at ground level.
Corydalis; 4 species in Wisconsin.
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