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  Lamiaceae: Monarda fistulosa

  R. Neil Reese

  Monarda fistulosa is an aromatic, rhizomatous perennial herb with simple to branched, square stems, 30-120 cm tall, the upper portions hairy. The simple, opposite leaves are petiolate (10-25 mm long). The blades are lanceolate to ovate, 2-5 cm long and 4-20 mm wide, with small glands, a pointed tip, and toothed to subentire margins. The inflorescence is a terminal cluster of flowers on the main stem and branch ends, 1-5 cm wide, excluding the corollas, and subtended by green to whitish bracts, 1-2.5 cm long. The calyx forms a hairy tube, 5.5-11 mm long with teeth up to 1.5 mm long. The pale to dark lavender (rarely white) bilabiate corolla is 2-3.5 cm long, the outer surface hairy, the tube at the base slender, 15-25 mm long, the upper lip erect and shorter than the tube, and the lower lip is spreading, 3-lobed. The stamens are exerted from the upper lip. The fruit are 4 brown to black nutlets, 1.5-2 mm long. Beebalm blooms from June into September on prairie hillsides, along roads and open woodlands in most of South Dakota.

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  Lamiaceae : Nepeta cataria

  R. Neil Reese

  Nepeta cataria is a perennial herbaceous plant growing from a fibrous root system, 40 to 100 cm tall with square, branched stems covered in fine hairs. The opposite leaves are ovate to heart-shaped, 3 to 7 cm long and 2 to 5 cm wide, serrated along the margins, and slightly hairy; they release a strong minty aroma when crushed, due to the presence of nepetalactone. The flowers are tubular and bilabiate, arranged in dense, spike-like verticillasters along the upper stems, blooming from late spring through early fall (June–September). Each flower has a calyx composed of five sepals fused into a tubular structure 5 to 7 mm long, with five distinct teeth. The corolla consists of five petals fused into a bilabiate tube 10 to 15 mm long, pale lavender to white with darker purple markings on the lower lip. There are four didynamous stamens (two long and two short), attached near the base of the corolla tube. The pistil consists of a superior ovary with a single style about 4 to 6 mm long, terminating in a bifid stigma approximately 1 to 2 mm wide; the stigma lobes are rounded. The fruit is a schizocarp divided into four smooth, shiny, brown nutlets approximately 2 to 3 mm long. Catnip is an introduced species in South Dakota, commonly found in disturbed sites, roadsides, and open fields throughout much of the state; it is native to Europe and Asia.

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  Lamiaceae :Stachys pilosa

  R. Neil Reese

  Stachys pilosa is a perennial, herbaceous plant with a fibrous root system and short, creeping rhizomes, forming loose, spreading clumps. Mature plants typically reach 30–90 cm in height. Stems are square in cross-section, erect, usually unbranched below the inflorescence, and densely covered with long, soft, spreading hairs (pilose). Leaves are opposite, simple, ovate to lanceolate, 4–12 cm long and 1–4 cm wide, with coarsely toothed margins and a rounded to slightly cordate base. The upper surface is medium to dark green and softly hairy, while the lower surface is paler and densely hairy. Petioles are present, 1–3 cm long, also covered with hairs. Stipules are absent. Flowering occurs from June to September, with dense, terminal and axillary spikes (verticillasters) 3–10 cm long, each containing many whorls of small, tubular flowers. The calyx is tubular, 7–10 mm long, with five narrow, pointed lobes, green, hairy, and slightly glandular; lobes are equal and not strongly spiny. The corolla is two-lipped (bilabiate), 12–16 mm long, pink to lavender, with the upper lip arched and the lower lip spreading and three-lobed. There are four stamens (didynamous: two longer and two shorter), about 7–10 mm long, with white to pale pink anthers. The pistil is single, with a deeply four-lobed ovary, a slender style 12–15 mm long, and a two-lobed stigma. The fruit is a cluster of four small, brown nutlets, each 2–3 mm long, maturing from late summer into fall. Downy woundwort is native to South Dakota and is found in prairies, open woodlands, roadsides, and moist, disturbed habitats, often in moderately rich, well-drained soils and full to partial sun.

  Synonym: Stachys palustris ssp. pilosa

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  : Lamiaceae: Teucrium canadense

  R. Neil Reese

  Teucrium canadense is a perennial, erect, herbaceous plant that spreads via an extensive system of slender, pale rhizomes coupled with fibrous roots. The plant typically reaches a height of 30 to 100 cm, featuring stout, unbranched or sparsely branched, square stems that are hollow and densely covered in downward-pointing or spreading hairs. Leaf insertion is opposite along the stem. The leaves are simple, lanceolate to ovate, medium-to-dark green above and paler beneath, measuring 5 to 13 cm long and 2 to 5 cm wide. The leaf margins are coarsely serrate. The upper leaf surface is finely pubescent to wrinkled, while the lower surface is densely covered in velvety, grayish-white hairs. The leaves have petioles measuring 0.5 to 1.5 cm in length. Flowering occurs from June through September, with the blossoms arranged in a dense, crowded, terminal spike-like raceme spanning 5 to 20 cm in length. The calyx is 5 to 7 mm long, composed of 5 fused sepals that form a bell-shaped tube with 5 unequal, short, triangular teeth; it is variable in color from light green to purplish-tinted and covered in sticky, glandular hairs. The corolla is 10 to 15 mm long and consists of 5 petals that are fused at the base but split into a highly irregular, bilaterally symmetrical configuration. The corolla upper lip is deeply cleft and reduced to two tiny lateral lobes. The lower lip is highly prominent, elongated, downward-projecting, pale pink to lavender-pink or purplish, often decorated with dark rose nectar guides. Emerging from the deep cleft of the reduced upper lip are 4 strongly arched stamens with slender, pinkish-white filaments that extend well beyond the corolla tube, terminating in tiny, orange-to-brown anthers. Nestled among the stamens is a single compound pistil with a deeply 4-lobed ovary, a long, slender, curving style, and a shortly two-cleft stigma. The fruit is a cluster of 4 small, dry, egg-shaped nutlets (schizocarp) that do not split open when ripe, each nutlet measuring about 2 mm long, finely wrinkled, tan to dark brown, and reaching full maturity from August through October. American germander is a native species in South Dakota, found statewide but occurring most frequently in the eastern and southern regions of the state; it primarily occupies moist-to-wet habitats including floodplains, wet prairies, marshes, ditches, stream banks, and damp woodland borders.

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  Liliaceae : Allium cernuum

  R. Neil Reese

  Allium cernuum is a perennial herb, which grows from a membranous bulb with stems 30 cm to 45 cm in height, that are usually bent just below the cluster of flowers. Each mature bulb typically bears a single flowering stem with up to 30 flowers. The leaves are keeled grass-like, flat or channeled and 2-4 mm wide. Flowers emerge from a membranous spathe in July and August, with the umbel nodding or laterally projected. The tepals are 3-5 mm long and white to pink in color. The 6 stamens are exerted from the tepals, and the ovary is prominently 6-crested. The fruit is a 3 valved capsule. This species is commonly found throughout much of Northern America in mountainous and cool regions, on ledges, gravels, rocky or wooded slopes and crests. Because of its wide distribution, it is variable in plant size, flower color and bloom time.

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  Liliaceae: Allium stellatum

  R. Neil Reese

  Allium stellatum is a perennial herb, arising from a bulb as a leafless scape growing from 20 to 60 cm tall. The stem is surrounded by grass-like lanceolate basal leaves that are up to 30 long. The leaves die back as the rounded umbel of pink to purple flowers emerge at the end of the scape in late summer. The umbel is 5–8 cm across, and each of the flowers has 6 tepals that flare outward and are about 6 mm long. The stamens are exerted, and the pistil has 6 locules. The fruit is a capsule with usually 1 seed per locule. This species is commonly found on prairies and hillsides.

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  Liliaceae : Allium textile

  R. Neil Reese

  Allium textile is a perennial herb coming from an underground egg-shaped bulb that is up to 2.5 cm long. This onion is shorter than the other common onions growing in South Dakota, often having multiple stems coming from a single bulb which grow from 10 to 30 cm in height. The stems are often curved or twisted in appearance. The plant has 1 or 2 flat grass-like leaves that are (2) 1-3 mm wide, alternately attached near the base, sheathing the stem, and may appear to be basal. Allium textile has numerous flowers arranged in a compact umbel and bloom from May to June.. The tepals are white to rarely pink in color, 5-7 mm long. The stamens are not exerted from the tepals as with the other common onions of the region. The fruit is a capsule. This species is commonly found throughout the state in mixed grass prairies, sagebrush steppes, meadows, open pine forests, and clearings.

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  Liliaceae : Calochortus nuttallii

  R. Neil Reese

  Calochortus nuttallii is a perennial herb growing from a membranous coated bulb, 14-44 cm in height. The 2-4, simple, alternate leaves are linear, 8-16 cm long and 1-2 mm wide, reduced in length toward the top. The inflorescence is a single terminal flower {occasionally 2-3), white with a yellow base, the outer whorl of tepals (sepals) are lanceolate, 20-33 mm long and 4-8 mm wide. The inner 3 tepals are obovate with a narrow base, 30-45 mm long and 27-38 mm wide, with a round gland surrounded by a fringed membrane covered with simple and/or branched hairs. The 6 stamens have filaments 5-8 mm long and anthers 5-10 mm long. The fruit is a linear-lanceolate, dehiscent capsule, 3-5 cm long. Sego lilies bloom in June and July on dry prairies and open woods in western South Dakota.

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  Liliaceae : Hypoxis hirsuta

  R. Neil Reese

  Hypoxis hirsute is a perennial herb growing from a rounded, membranous coated corm. There is a rosette of 3-6 basal, linear leaves, 5-26 cm long and 2-12 mm wide, green with scattered white hairs. The plants produce one to several slender flowering stems (scapes), up to 20 cm tall, each with a 2-14 flowers in a terminal umbel. The flowers have 6 yellow tepals, 6-14 mm long and 2-6.5 mm wide, with hairs on the outer surfaces. There are 6 stamens, the filaments 2-3 mm long and the anthers 2-4 mm long. The ovary is inferior and hairy. The fruit is a hairy, ovoid capsule. Yellow stargrass blooms from April into July on prairies and in open deciduous woodlands in eastern South Dakota.

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  Liliaceae : Maianthemum racemosum

  R. Neil Reese

  Maianthemum racemosum is a perennial herb from a whitish rhizome with simple, erect stems growing 35-80 cm tall. The simple, alternate, lanceolate to elliptical leaves are 2-ranked, 6-15 cm long and 2-7 cm wide. The leaves are sessile or with a short petiole, have a rounded bases, a pointed tips, and entire margins, with prominent veins running the length of the leaves. The inflorescence is a many-flowered panicle. The flowers have 6, white tepals, 1-4 mm long and 6 stamens that are longer than the tepals. The fruit is a green to red to purple berry, 4-6 mm in diameter. False Solomon’s Seal blooms from April into July in moist woodlands and thickets in the eastern and western border counties of South Dakota.

  Synonym: Smilacina racemosa

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  Liliaceae : Maianthemum stellatum

  R. Neil Reese

  Maianthemum stellatum is a perennial herb from a whitish rhizome with simple, erect stems growing 15-65 cm tall. The simple, alternate, lanceolate to oblong leaves are 2-ranked, 4-16 cm long and 1-4 cm wide. The leaves are sessile, folded, have pointed tips, and entire margins, with a prominent central vein. The inflorescence is a raceme, sessile or with a short peduncle. The flowers have 6, creamy white to greenish white tepals, 4-7 mm long and 6 stamens are 2-5 mm long, shorter than the perianth. The fruit is a berry, 7-9 mm in diameter, initially light green with blue stripes and turns dark blue purple as it ages. Starry false Solomon’s Seal blooms in May and June in moist to dry woodlands, along streams and rivers throughout much of South Dakota.

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  Liliaceae: Ornithogalum umbellatum

  R. Neil Reese

  Ornithogalum umbellatum is a perennial, scapose herbaceous forb that arises from a subterranean bulbous root system; the main globose bulb is typically surrounded by numerous small, clustered ovoid offsetting bulbils. The plant reaches a height of 15 to 30 cm. It features an erect, glabrous, unbranched, leafless stem (scape) that emerges directly from the basal tufted rosulate leaf clusters. The leaves are simple, linear, elongate, succulent, and glabrous. They exhibit a deep green color, accented by a prominent, light green to white central midvein running along the upper surface. Each leaf blade measures 20 to 60 cm in length and 2 to 8 mm in width, tapering to a point, and lacking a distinct petiole. Flowering occurs from April to June, with individual flowers opening in the late morning or afternoon. The inflorescence is a terminal, flat-topped corymbose raceme spanning 5 to 10 cm across, supporting 3 to 20 flowers on ascending pedicels. The perianth consists of 6 free, distinct, petaloid tepals arranged in two whorls of 3. The outer 3 tepals are lanceolate-oblong, 15 to 30 mm long and 3 to 5 mm wide, featuring a bright white upper surface and a broad, distinguishing longitudinal green stripe on the lower surface. The inner 3 tepals share an identical size, shape, and color scheme. The androecium consists of 6 distinct stamens; the filaments are white, flattened, and petaloid, measuring about 5 to 8 mm long, capped by small, pale yellow anthers. The gynoecium features a single pistil with a superior, deeply 6-ribbed, 3-locular ovoid ovary, a short, stout style, and a capitate, 3-lobed stigma. The fruit is an erect, 3-valved, obovate to oblong capsule measuring 8 to 18 mm in length, remaining green until it dries to a yellowish-brown color upon reaching maturity in mid-to-late summer (June to July). The garden star-of-Bethlehem is not native to South Dakota; it is an introduced species native to Europe, North Africa, and the Middle East. It has naturalized locally in southeastern and central South Dakota, primarily invading disturbed areas, lawns, gardens, old homesites, pastures, open woodlands, and semi-shaded stream banks.

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  Liliaceae : Trillium cernuum

  R. Neil Reese

  Trillium cernuum is a perennial herb from a short rhizome, the stem 30-50 cm tall, topped with a whorl of 3 terminal leaves. The simple, leaves are rhombic-obovate, 6-12 cm long and wide, with a petiole-like base and usually have a sharp tip. The flowers hang beneath the leaves on peduncles 3-4 cm long. The 3 green sepals are broadly lanceolate, 1.5-2 cm long. The 3 white petals are oval to obovate and 1-3 cm long. The 6 stamens have anthers and filaments that are each 4-5 mm long. The fruit is a berry, about 3 cm in diameter, that starts out white and ripens to a deep red. Nodding trillium blooms in June and July in the moist deciduous woods along the coteau des prairies in eastern South Dakota.

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  Liliaceae : Uvularia grandiflora

  R. Neil Reese

  Uvularia grandiflora is a perennial herb growing from a rhizome and thickened fibrous roots, with simple to occasionally branched stems, 35-70 cm tall. The simple, alternate, ovate oblong to elliptic leaves are 6-12 cm long and 2-6 cm wide, smooth on top and hairy below. The leaf margins are entire and membranous. The solitary flowers are terminal and drooping. There are 6 yellow tepals that appear twisted, 2.5-4.5 cm long, the tips pointed, with 2mm diameter nectaries toward the base. The 6 stamens are shorter than the petals. The fruit is a 3-lobed capsule containing several rounded seeds. Large bellwort blooms in April and May in moist woodlands along the eastern edge of South Dakota.

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  Liliaceae : Zigadenus elegans

  R. Neil Reese

  Zigadenus elegans is a perennial herb from a deep, truncated, fibrous coated bulb, with stems growing 10-70 cm in height. The simple, alternate leaves are linear, 10-35 cm long and 2-10 mm wide, with roughened margins. The basal leaves are folded and the cauline leaves flat. The inflorescence is a raceme (rarely a panicle) with few to numerous flowers. The 6 greenish white tepals are oval to obovate, 6-8 mm long with a 2-lobed dark green gland toward the base. The 6 stamens arise from the base of the partially inferior ovary. The fruit is a capsule 15-20 mm long. Death camass blooms from June into August in the plains, prairies and open conifer forests in counties along the eastern and western edges of South Dakota.

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  Linaceae : Linum lewisii var. lewisii

  R. Neil Reese

  Linum lewisii var. lewisii is a perennial with stems branching at the base and growing 20 to 80 cm in height. The simple, linear to linear lanceolate leaves are 1-3 cm long, alternate above and crowded on the lower portions of the stem where they can appearing whorled. The leaf margins are entire and the apex is pointed. The inflorescence is a panicle with few branches and spreading pedicels. The 5 sepals are green and 3.5-5 mm long. The 5 petals are blue (occasionally white), 10-15 mm long, with the stamens opposite them. The fruit is an ovoid capsule, 5-7 mm long, that separates into 10 segments. Prairie flax blooms from May into August in prairies and on open wooded hillsides in the eastern and western border counties of South Dakota.

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  Loasaceae : Mentzelia decapetala

  R. Neil Reese

  Mentzelia decapetala is a coarse, erect, shrubby looking, biennial to weakly perennial herb growing up to 1 m tall. There are 1 to several stems that branched above, and the lower stems develop a whitish, exfoliating bark. The leaves are alternate, fleshy, lanceolate, 4-15 cm long, 1.5-4 cm wide, pinnatifid with wavy lobes, the lower leaves petiolate and the upper sessile. The flowers are solitary or in small clusters at the ends of branches. The 5 sepals are 1-5 cm long with pointed tips, and the 10 petals are white to cream colored, 5-7 cm long and 1-2 cm wide, oblanceolate to spatulate and often overlapping. There are numerous stamens that are shorter than the petals and form a yellow center in the opened flower. When open, the petals create a showy display, each flower up to 15 in diameter. The flowers open in late afternoon and close around midnight. The fruit is a cylindrical capsule 3-5 cm long and 1,5-2 cm wide with numerous, flattened, minutely winged seeds. Ten-petal blazingstar blooms from July into September along roadsides, and other disturbed places, including the Missouri River drainage, scattered throughout South Dakota.

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  Lythraceae: Lythrum salicaria

  R. Neil Reese

  Lythrum salicaria is a hardy perennial herbaceous forb that develops a dense, woody taproot system anchored alongside a thick, creeping rhizome network capable of forming massive clonal colonies. The plant typically reaches heights of 1 to 2.5 m and bears stiff, erect, distinctly 4-to-6-angled square stems that display ascending branches and become subwoody and sparsely to densely pubescent with age. Leaf insertion is primarily opposite or arranged in whorls of 3, transitioning to alternate near the stem apex. The simple, lanceolate to ovate-lanceolate leaves are medium-green, 3 to 10 cm long, 1 to 2.5 cm wide, feature smooth entire margins, have rounded to heart-shaped subclasping bases, and lack petioles. The leaf blades are downy pubescent to weakly tomentose on both upper and lower surfaces. Flowering occurs from June through September. The showy terminal inflorescence spike that spans 10 to 40 cm in length. The persistent sepals are fused into a tubular, heavily veined 5-to-7-toothed calyx tube (hypanthium) measuring 4 to 6 mm long, shaded green to dull purple, and with narrow appendages between sepals that are 2.5 to 3 mm long and extend past the sepals. The 5 to 7 petals are free, obovate, wrinkled, magenta-pink to deep purple, and measure 7 to 12 mm long and 2 to 4 mm wide. Flowers contain 12 stamens arranged in two distinct whorls of alternating lengths (short, medium, or long) featuring yellow to greenish-purple filaments and dark anthers. The single compound pistil contains an ovary with a long, medium, or short style topped by a green, capitate stigma. The fruit is an oblong, 2-valved capsule measuring 3 to 5 mm long, which transitions from green to a dry, papery brown at maturity. Fruit capsules ripen progressively from late July through October, splitting open to release hundreds of microscopic, brown, hairless seeds. Purple loosestrife is not native to South Dakota. It is an aggressive, introduced weed native to temperate Eurasia and northern Africa that has naturalized along the Missouri River, urban drainage basins, and lake shores across southeastern and western South Dakota. It thrives in wet, sunlit habitats including marshes, wet meadows, prairie potholes, riverbanks, and roadside ditches.

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  Malvaceae : Sphaeralcea coccinea

  R. Neil Reese

  Sphaeralcea coccinea is a deep-rooted perennial herb with 1 or more decumbent to ascending stems growing from a woody caudex, reaching up to 50 cm in length, and usually covered with small hairs. The alternate, petiolate leaves are covered with hairs, irregularly divided 3-5 times, with the lobes divided again or merely toothed. The leaf blade’s overall outline is 1-6 cm long and about as wide or even wider, with the final narrow segments being oblong to oblanceolate. The inflorescence is a raceme, 2-11 cm long, and usually without subtending bracts. The flowers have short pedicels, a tubular calyx 3-10 mm long with 5 lobes that are equal to or longer than the tube. The 5 deep orange to brick red petals are 1-2 cm long and notched. There are numerous stamens, fused at the base, and 10 or more carpels, 3-3.5 mm tall, with stellate hairs at maturity. The fruit is a schizocarp. Scarlet globemallow blooms from April into August on dry prairies, plains and on hillsides in much of South Dakota.

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  Monotropaceae: Pterospora andromedea

  R. Neil Reese

  Pterospora andromedea is a non-photosynthetic, leafless, perennial, parasitic herb growing 20 to 60 cm tall from a thick, fleshy rootstock that forms a mycorrhizal association with certain pine species. The erect stem is reddish to brownish and covered with glandular hairs, branching near the top. Instead of true leaves, it bears scale-like bracts along the stem. The inflorescence is a dense raceme of nodding, urn-shaped flowers blooming from May through August. Each flower measures about 1.5 to 2.5 cm long, with five fused petals, 12 to 18 mm long, forming a pale cream to reddish bell-shaped corolla. The calyx consists of five small, persistent, triangular, greenish to reddish, lanceolate sepals, 3 to 5 mm long, beneath the corolla. Flowers have 10 stamens inserted on the corolla tube, with filaments alternating in length and the anthers are yellow. The style is slender, extending beyond the stamens, terminating in a bilobed stigma. Fruits are capsules, 8–12 mm long, maturing from August through September and contain numerous tiny seeds. Native to South Dakota, Pinedrops is found primarily in coniferous forests, especially under pine trees where its fungal host grows, mainly in the Black Hills and western regions of the state.

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  Nuttallanthus canadensis

  R. Neil Reese

  Linaria canadensis is a winter annual or biennial, upright, non-woody, herbaceous plant that develops from a shallow, fibrous taproot system. The plant reaches a mature height of 25 to 80 cm. It generates both prostrate, non-flowering basal rosette stems and one to several slender, erect, simple or minimally branched flowering stems that are green to reddish-green, glabrous, and smooth. Leaf insertion varies across the plant, with leaves arranged oppositely or in whorls along the prostrate basal shoots, while shifting to an alternate arrangement on the upright flowering stems. The simple leaves are bright green, linear to oblong-linear, 10 to 35 mm long, and 1 to 3 mm wide with smooth, slightly thickened margins. Both upper and lower leaf surfaces are completely glabrous, and the leaves are sessile. Flowering occurs from mid-spring to mid-summer (typically March to July). The inflorescence is a slender, terminal raceme that spans 5 to 20 cm long. The calyx consists of 5 green, free to minimally fused sepals that are lanceolate to oblong-linear, acute at the apex, glandular-pubescent, and measure roughly 2 to 3 mm long and 1 mm wide. The corolla features 5 fused petals forming a strongly bilateral, two-lipped structure that is pale blue to lavender purple (rarely white) with a distinct white palate on the lower lip. The upper lip is erect and 2-lobed (5 to 6 mm long), while the lower lip is prominent and 3-lobed (about 8 mm long) with a slender, backward-pointing nectar spur measuring 2 to 6 mm long at the base. Contained within the petal tube are 4 didynamous, hairless stamens that are short, white, and capped with small yellow anthers. There is 1 superior, 2-loculed pistil with a short, single style and a small, faintly 2-lobed stigma. The fruit is a smooth, subglobose, two-valved capsule measuring about 3 mm long and 3 mm wide. It matures from green to dark brown between April and September, splitting open at the apex to release hundreds of microscopic, smooth, flattened seeds. Blue toadflax is native to South Dakota, where it is found sparsely across southern and western counties (such as Jackson County) in highly disturbed, dry, open sandy fields, blowouts, and prairie hillsides.

  Synonym: Linaria canadensis

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  Nyctaginaceae: Mirabilis nyctaginea

  R. Neil Reese

  Mirabilis nyctaginea is a perennial herbaceous plant typically growing 30 to 90 cm tall. It has a thick, often tuberous root system that helps it survive dry conditions. The stems are erect or sprawling, branched, and covered with fine hairs. Leaves are opposite, ovate to broadly lanceolate, measuring about 4 to 12 cm long and 2 to 6 cm wide, with smooth or slightly wavy margins. The leaf surfaces are smooth to slightly hairy. Leaves are petiolate with slender petioles. The plant is named “four o’clock” because its flowers typically open late afternoon to evening and close by morning. The inflorescence consists of clusters of trumpet-shaped, tubular flowers that are usually cream, yellowish, or pinkish, blooming from summer to early fall (July–September). Each flower is about 2.5 to 4 cm long, with five fused petals forming a funnel shape, the lobes of the corolla are rounded and softly ruffled at the edges. Bracts subtend each flower cluster and are leaf-like, often with pointed tips. They measure 5-6 mm long at anthesis and grow to 1.5 to 3 cm long and 0.5 to 1.5 cm wide in fruit. The flowers are fragrant and attract moths for pollination. The fruit is a small, hard, three-lobed, one-seeded nutlet enclosed in a persistent, winged calyx (bracts). Wild four o’clock is native to South Dakota and commonly found in disturbed areas, roadsides, and open woodlands in much of the state, but is most often reported in central and eastern regions, where agricultural and roadside habitats provide ideal growing conditions.

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  Nymphaeaceae: Nuphar lutea

  R. Neil Reese

  Nuphar lutea is a perennial aquatic plant with stout, creeping rhizomes anchored in muddy substrates of freshwater ponds, lakes, and slow-moving streams. The floating leaves are orbicular to ovate, 10 to 25 cm long and 8 to 20 cm wide, with a heart-shaped base, thick and leathery with smooth margins and a smooth, glossy upper surface. The solitary flowers, borne on thick stalks rising above the water, have 4 to 6 broadly ovate sepals measuring 15 to 25 mm long, enclosing numerous bright yellow petals about 10 to 15 mm long and 3 to 5 mm wide, which are oblong to spatulate in shape and arranged in multiple layers. The flower contains 40 to 60 stamens with slender filaments and yellow anthers arranged in several concentric whorls around numerous free pistils. Each pistil has a short style and a small, rounded stigma. The fruit is an aggregate of achenes embedded in the spongy receptacle, maturing underwater into a berry-like structure, 3–6 cm in size, containing many small seeds released gradually as the fruits disintegrate. Yellow waterlily, as recognized by the USDA, is native to South Dakota, found in some natural and artificial wetlands, ponds, lakes, and slow-moving waters.

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  Onagraceae : Calylophus serrulatus

  R. Neil Reese

  Calylophus serrulatus is a perennial herb with few to many simple to branched, decumbent to erect stems, 5-80 cm long. The simple, alternate leaves are linear to lanceolate, 1-10 cm long and 1-12 mm wide, smooth to slightly hairy on top and generally hairy on the under surface. The blades are sessile to semipetiolate, the leaf tapering to the base and having a pointe tip, with margins that are entire to toothed. The 4-merous flowers are axillary in the upper parts of the stems. The sepals are 1.5-9 mm long and 2-6 mm wide, distinctly keeled, hairy below, with free tips 1-4 mm long. The 4 yellow petals are 5-20 mm long and about as wide. There are 2 series of stamens, one attached to the sepals and the other the petals, the former longer than the latter, and the stigma is ~2 mm wide in the center of the flower. The fruit is a capsule, 10-30 mm long and 1-3 mm wide. Yellow sundrops bloom from May into September on roadsides in rocky to sandy prairies and open woodlands in much of South Dakota.

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  Onagraceae : Chamerion angustifolium ssp. circumvagum

  R. Neil Reese

  Chamerion angustifolium ssp. circumvagum is a stout, erect perennial herb with simple to branched, red stems growing up to 3 m tall, that are smooth to occasionally having short, stiff hairs toward the top. This plant has an large root system, producing extensive colonies by forming shoots on lateral roots. The alternate leaves are lanceolate, with an acute tip, 2-20 cm long and 4-35 mm wide and arranged in a spiral. The leaves are sessile or nearly so, with a strong midvein and margins that are usually wavey. The inflorescence is a terminal many-flowered raceme. The slightly irregular flowers are drooping in the bud, the 4 spreading, green to purple sepals are lanceolate, 7-16 mm long and less than 3 mm wide. The 4 pink to magenta petals are obovate, tapering to a short claw, 10-20 mm long and 6-11 mm wide, usually with a notch. There are 8 slightly unequal stamens surrounding a pistil with a densely white haired ovary 8-18 mm long atop of a pedicel 4-12 mm long, with a white to purplish style, 10-20 mm long, with a ring of hairs at its base and topped by a 4-lobed stigma. The fruit is a capsule 4-10 cm long on a pedicel up to 2.5 cm long, containing may long-haired seeds. Fireweed blooms from June through September in open woodlands and disturbed areas, especially after fires in western South Dakota.

  Synonyms: Epilobium angustifolium, Chamaenerion angustifolium