**NOTE - Names in blue/purple have a picture of species seen in class, others have may a specimen within the same genus but a different species.  It should be mentioned that subtle differences may exist even within a species, so when in conflict always refer to live specimens seen in the lab!**

Alismataceae: Water Plantain Family
Alisma sp. - water plantain Click here for species from this genus
*seen in herbarium only; has two types of leaves, emergent leaves lance-shaped to oval on long petioles, leaves rounded or tapered at the base, submerged leaves ribbon-like; flowers in an umbel on numerous, rigid stems, pink; fruit an achene; muddy shores, streambanks, shallow marshes.

Sagittaria latifolia - arrowhead, duck potato Click here for species from genus
leaves variable emersed leaves arrow-shaped, have large lobes at the base, erect extending above the surface, arising from the base which is normally submersed, submerged leaves elliptical  to lance-shaped; inflorescence is a raceme of whorled white flowers with three roundish petals; fruit are winged achenes with a persistent style; ponds, shallow water, lakeshores, streambanks, and muddy shores.

Araceae: Arum Family
Peltandra virginica  - arrow arum, tuckahoe Click here for species from genus
leaves basal on long petioles, deeply lobed at base, each basal lobe with a heavy central vein, flowers white spadix with a fleshy green spathe, spathe is rolled over spadix; fruit a berry; herbs growing on muddy shores, shallow water, and bogs.

Pistia stratoites - Water Lettuce
*not seen in lab; floating plant, leaves basal, form a fan that resembles lettuce, waxy coating, an invasive tropical plant found in warmer regions, does NOT survive Michigan winters, seen only in horticultural ponds.

Asteraceae (Compositae): Aster Family
Aster sp. - aster Click here for species from this genus
leaves variable but usually lance-shaped with a tapering point, simple, alternate; flower heads with a yellow disk, rays are blue, purple, yellow, or white, fruit a flattened achene; variable habitats wet meadows, roadside ditches, streambanks.

Bidens sp. - begger-ticks
leaves variable mostly toothed and lance-shaped, opposite; flowers a ray or disk with involucral bracts, originating at leaf axils, extremely variable plant and difficult to get an exact determination on species; habitats variable, shores, swamps, wet meadows.

Cabombaceae: Water Shield Family
Brasenia schreberi - water shield
*seen in herbarium only; floating plant, underwater portions have a gelatinous coating, leaves oval shaped, floating with petiole attached to the center of blade; flowers purple from leaf axils; fruit oblong capsule; quiet ponds and lakes.

Campanulaceae: Bellflower Family
Campanula aparinoides - marsh bellflower Click here for species from this genus
stem weak, 3-sided, and rough to the touch; leaves linear or narrowly lance-shaped, leaves get progressively smaller as they go up the stem, attached directly to the stem (sessile); flowers solitary with a funnel-like shape, blue to white; fruit is a capsule; sedge meadows, marshes, fens, swamps, thickets, bogs.

Ceratophyllaceae: Hornwort Family
Ceratophyllum dermersum - coontail Click here for another species
plants submersed; leaves whorled, dichotomously forked with spiny teeth along one side, more crowded toward the tip giving the “coontail” appearance, leaves anchoring plant to substrate; flowers small and inconspicuous, fruit is achene, without roots; lakes, ponds, still/back waters.

Cyperaceae: Sedge Family
Cyperus rivularis (C. bipartitus) - shining flatsedge, nut grass
Spikelets flattened, spikelets horizontal  or pointing downward from the stem, each scale tinged with red, the scales in 2 rows on opposite sides of the rachilla; rachilla often with thin wings somewhat enclosing the achene or running to the scale next above; habitat variable, often found on edges of open waters or in marshy areas.

Eleocharis sp. - spike rush Click here for a species from this genus    Click here for another species
leaves are without blades and represented by sheaths at the base of the stem; stems may be round or angled; flowers are solitary terminal spikelets, flower has subtending scale which hides it from view, arranged spirally on the axis of the spikelet with overlapping scales, the style base of each ovary persists as a tubercle on the mature fruit; identification within the genus is impossible unless the achene is mature because species identification is based on the tubercle characteristics; shallow and deep marshes, muddy, sandy shores, ponds, stream banks, wet meadows, swales.

Scirpus americanus - three-square bulrush
stems with sheaths at base, up to a meter tall, erect, sharply 3-angled; involucral bract of a single leaf looks as if it is part of the stem (may be short); spikelets several; scales of spikelet red-brown; achene with abrupt short point; shallow and deep marshes, shores.

Haloragidaceae: Water-milfoil Family
Myriophyllum sp.- water milfoil Click here for a species from this genus  Click here for another species
tems simple or branched, submerged or sometimes floating or ascending; leaves variously arranged, usually whorled and pinnately compound; flowers imperfect; inflorescence terminal or in axils; fruit is a nut; mostly submerged.
*Note Myriophyllum spicatum is an invasive species similar in appearance found along with the native species

Hydrocharitaceae: Frog's-bit Family
Elodea sp. or Anacharis sp. - waterweed Click here for a species from this genus
plants submersed; branching stems forming large masses at the bottom; leaves whorled (occasionally); flowers from a spathe, pistillate with a long thread-like tube reaching surface, male and female on separate plants (dioecious); shallow to deep waters, shores, ponds, shallow marshes.

Vallisneria americana - wild celery, tape grass, eel-grass
plants submersed; leaves long and strap-like, no stems; plants male or female; female produce flowers in a spathe which float at surface and is attached to long peduncles, male plants produce flowers which are released under water and rise to surface to float freely; fruit a capsule; lakes and streams.

Lamiaceae (Labiatae): Mint Family
Lycopus sp. - cut-leaved water horehound Click here for a species from this genus
leaves opposite, lance-shaped, deeply serrated, petioles very short to absent, tiny gland-like dots found on upper surface of leaves; square stems; without mint odor; flowers small in whorled clusters in leaf axils, corolla is a tube usually with two flaring lips (bilabiate); fruit a nutlet; marshes, wet meadows, shores, streambanks, ditches, fens, and wetland margins.

Lemnaceae: Duckweed Family
Lemna minor - duckweed
floating; with roots; without leaves; fronds have one root to each joint, round to obovate; green underneath; 2-5mm long; joints rounded, not stalked, fruit a utricle; float until cold weather; shallow marshes, ponds, stagnant waters.

Najadaceae: Water Nymph Family
Najas sp.- water nymph Click here for species from this genus
slender, branched, submersed, aquatic plants, with narrow opposite leaves dilated (widened) at the base and minute axillary flowers which are surrounded by a sheathing leaf base; fruit is an achene; ponds, lakes, streams, marshes.

Nymphaeacea: Water-Lily Family
Nuphar sp. - Yellow Water Lily, spatterdock Click here for species from genus
Petals many, much smaller than the sepals, usually shorter than the stamens. Stamens numerous.  Aquatic plants from stout rhizomes, with basal leaves either floating, or emergent, with long petioles, cordate leaves; yellow to purplish or red flowers solitary on long peduncles; fruit an ovate berrylike capsule; lakes, ponds, quiet waters.

Nymphaea odorata - fragrant water lily
platter-like large floating leaves, nearly orbicular in shape with a v-shaped cleft (notched); rhizome thick and fleshy; floating flower is white, fragrant with numerous petals and stamens; fruit berrylike capsule; shallow water of ponds and lakes, quite water in rivers.

Pontedariaceae: Water-hyacinth Family
Eichornia crassipes - water hyacinth (tropical)
*not seen in lab; stems and leaves floating, emerged or  creeping; inflorescence a spike or panicle; found in many aquatic habitats. *a nuisance plant in Florida and other tropics.  Seen in horticultural garden only, but worth noting as it is common on warmer regions.

Heteranthera dubia - Water Star-grass
submergent; inflorescence one-flowered, nearly sessile, completely enclosed by the spathe, sessile in the leaf axil,  flowers regular; perianth salverform;  submersed plant with linear, pellucid, grass-like leaves, alternate, the small flowers expand on the water-surface; fruit a utricle; shallow water of lakes, ponds, rivers, and swamps.

Pontedaria cordata - pickerelweed
leaves clustered, large, arrow or heart-shaped (cordate) with numerous parallel veins, extending erect above the water surface; flowering stems consist of a single leaf and a dense spike of blue/purple bilabiate flowers within a spathe; fruit a utricle; rivers, swamps, lakes, shallow water.

Potamogetonaceae: Pondweed Family
Potamogeton sp. - pondweed Click here for species from this genes
leaves may be in two types, floating and firm or submersed and thin/membranous; flowers borne in spikes ascending above the water surface for wind pollination, flowers in numerous pencil-like spikes, conspicuous in early to mid summer, retreating beneath the surface when the fruit matures; fruit an achene; identification is difficult; shallow marshes, ponds.

Potamogeton amplifolius - big-leaf pondweed
plants submersed; leaves in three types, underwater leaves in two shapes, upper underwater leaves ovate, and often folded into a crescent or sickle shape, lower underwater leaves lance-shaped, and decay rapidly (often not seen), floating leaves ovate and either rounded or tapered (acuminate) at the tip, rounded base; flowers in dense spikes; fruit a beaked achene; shallow water of lakes and rivers.

Potamogeton crispus - curly pondweed
leaves and stems all submerged; leaves oblong, rounded at tip, clasping at base, margins wavy (undulate) or toothed; flowers in spikes; fruit a beaked achene; lakes (including Great Lakes) and rivers.  Commonly found in populated areas.

Potamogeton illnoensis - illinois pondweed
plants submersed; leaves in two types, underwater leaves variable, lance-shapedshaped to obovate; floating leaves lance-shaped to oval, the leaf bases are variable wedge-shaped or rounded; flowers in dense spikes; fruit a short-beaked achene; shallow water to deep water of lakes and rivers.

Potamogeton natans - floating-leaf pondweed
plants submersed; leaves in two types, underwater leaves reduced to large, expanded petioles (phyllodes), floating leaves ovate to oval with a short point, heart-shaped (cordate) at base; flowers in dense spikes; fruit a beaked achene; shallow water of ponds and lakes.

Potamogeton pectinatus - sago pondweed
plants submersed; leaves submersed type only, underwater leaves ribbon-like (filliform); flowers in dense spikes; fruit a beaked achene; shallow to deep lakes, ponds, and streams.

Potamogeton richardsonii - clasping-leaf pondweed
plants submersed; leaves all submerged, lance-shaped, base is heart-shaped (cordate) and clasps the stem (sessile), fruit a short-beaked achene; shallow to deep water of lakes (Including Great Lakes) and streams.

Sparganiaceae: Bur-reed Family
Sparganium sp. - bur-reed Click here for species from this genus
leaves long, ribbon-like, clustered basally, fairly thick if erect (sometimes limp), extending above the surface up to 1.5m tall; lower pistillate flowers in bur-like, spherical heads, upper staminate flowers form separate smaller balls, whitish-greenish-brown; fruit is an nutlike achene; mature fruit is needed for identification to species; fens, shallow marshes, swales, ponds.

Typhaceae: Cat-tail Family
Typha angustifolia - narrow-leaved cattail  Click here for another species
leaves long and ribbon-like; stem is slender, underground stems spread rapidly;  flowers small and unisexual, arranged into close cylindrical spikes which consist of an upper region of staminate (male) flowers and a lower region of pistillate (female) flowers in a dark brown spike (the male flower falls off after pollination), staminate and pistillate portions are usually divided by at least 5 mm; wet ground shallow and deep waters; sign of disturbance; food for muskrats and cover for many types of wildlife.