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  Juglandaceae : Juglans nigra

  R. Neil Reese

  Juglans nigra is a large tree with brown bark that grow to 25 m tall with a trunk up to 1 m in diameter in a forest stand. Individual specimens growing under ideal conditions can grow much larger. Young twigs are green and covered with glandular hairs. The alternate, compound palmate leaves grow to 50 cm long, the 11-23 leaflets are sessile, oblong lanceolate, pointed at the tip and usually with small teeth along the margins. The trees are monoecious, with green male flowers in catkins up to 12 cm long, each with about 4 sepals and 8-40 stamens. The female flowers are terminal on new growth in clusters of 1-several flowers, each with 3 small bracts and a hairy pistil with a short style and 2 yellow green stigmas. The fruit is a globose, yellow green turning brown nut, 5 cm in diameter, containing a nut 4 cm in diameter. Black walnut blooms in April and May. This species is native to the southeastern corner of South Dakota, but has been planted in windbreaks and yards state wide, becoming naturalized throughout the state.

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  Juncaceae: Juncus torreyi

  R Neil Reese

  Juncus torreyi is a perennial herbaceous rush form loose colonies from a creeping rhizome, with stiffly erect, unbranched culms 30-80 cm tall. There are 1-3 basal leaves and 2-5 alternate leaves on the culms. Leaves are round in cross-section, often longer than the culms, with cross partitions at regular intervals. The sheath is open at the front with a pair of rounded lobes, 1-4 mm long. The inflorescence consist of 1-many flower heads in a tight cluster at the top of the stem. Each flower head is 1-1.5 cm in diameter, round, with up to 100 flowers. Each flower has 6 tepals, green to straw-colored, drying to dark brown, in 2 whorls, the outer set longer than the inner set. There are 6 stamens, a 3-parted style and the fruit is a capsule. Torrey’s rush blooms from June into October along lakes, streams in wet prairies and ditches throughout South Dakota.

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  Lamiaceae: Agastache foeniculum

  R. Neil Reese

  Agastache foeniculum is a perennial rhizomatous herb, which grows 0.6 m to 1 m in height. The stems are square with opposite ovate to broad to lanceolate simple leaves, greenish above and whitish underneath due to fine, appressed hairs the leaf margins are finely toothed. When crushed the leaves smell of anise. Flowers open in July and August and are arranged in a terminal spike-like raceme. The tubular calyx is 5 toothed 5-7 mm long and lavender toward the tips. The corolla is 2-lipped 7-10 mm long and lavender to bluish-purple in color. Stamens 4 and exerted from corolla. Pistil with 2 carpels with a 2-part style. Fruit are 4 nutlets. Lavender hyssop blooms from June through September. This species is commonly found in upland woods and prairies in both eastern and western South Dakota.
  
  
  

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  Lamiaceae: Glechoma hederacea

  R. Neil Reese

  Glechoma hederacea is a perennial, creeping herbaceous plant that spreads by stolons, forming dense mats on the ground. Stems are square in cross-section, typically reaching 10–50 cm in length, hairy, and spreading laterally or creeping along the soil surface, often rooting at nodes. Leaves are opposite, rounded to kidney-shaped with scalloped edges, 2–4 cm across, and aromatic when crushed. Flowering occurs from spring to early summer (April–June). The flowers are small, tubular, and bilaterally symmetrical, borne singly or in small clusters from leaf axils. They are typically light purple to bluish with darker purple markings on the lower lip. Each flower has five sepals and five petals. The sepals form a tubular calyx about 0.5–1 cm long, with five pointed lobes that are lanceolate in shape. The petals are fused into a two-lipped corolla about 1–1.5 cm long: the upper lip is hooded and two-lobed, while the lower lip spreads out and is three-lobed with a slightly notched center lobe. Flowers are bisexual with four stamens and a single, superior ovary formed from two fused carpels, which develops into a four-lobed schizocarp fruit that splits into four one-seeded nutlets that mature in late summer. Ground ivy is introduced and widespread in South Dakota, found in lawns, gardens, roadsides, and shaded disturbed areas.

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  Lamiaceae: Lamium amplexicaule

  R. Neil Reese

  Lamium amplexicaule is an annual herbaceous plant growing 10 to 40 cm tall with a fibrous root system. The stems are square in cross-section, sprawling to ascending, and covered with fine hairs. Leaves are opposite, simple, and broadly ovate to orbicular with rounded or slightly lobed margins, measuring about 2 to 5 cm long and wide. Leaves are sessile, clasping the stem (amplexicaul). The leaf surfaces are hairy and rough to the touch. The inflorescence consists of whorls of tubular, two-lipped flowers arranged in leaf axils, flowering from early spring to early summer (March–June). The calyx is composed of five sepals fused into a tubular cup about 5 to 8 mm long, with five pointed lobes that are ovate-lanceolate in shape and covered with fine hairs. The corolla is bilabiate, about 1 to 1.5 cm long and 0.5 to 0.8 cm wide, with the upper lip forming a hood that is broadly ovate and rounded, while the lower lip is three-lobed with the central lobe being the largest and slightly notched. The petals are pink to purple with darker markings on the lower lip. The flowers have four stamens, two long and two short, and a superior ovary with a bifid style. The fruit is a schizocarp that splits into four nutlets. In South Dakota, Henbit deadnettle is an introduced species, native to Eurasia, commonly found in disturbed sites, lawns, gardens, fields, and roadsides statewide.

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  Lamiaceae: Leonurus cardiaca

  R. Neil Reese

  Leonurus cardiaca is a perennial herbaceous plant growing 0.5 to 1.5 meters tall. It has a fibrous root system with occasional short rhizomes. The stems are square in cross-section, erect, and typically covered with fine hairs. Leaves are opposite, simple, and palmately lobed with 3 to 5 deep lobes, measuring about 5 to 12 cm long and wide. Leaves are petiolate, with petioles approximately 2 to 5 cm long, and the leaf surfaces are sparsely to moderately hairy. The leaf margins are coarsely toothed. The inflorescence is a dense, interrupted spike of whorled flowers around the stem, flowering from mid to late summer (June–August). The calyx consists of five sepals fused into a tubular base about 4 to 7 mm long with five triangular-ovate, pointed lobes covered in fine hairs. The corolla is tubular, bilabiate, measuring about 8 to 12 mm long and 5 to 7 mm wide, with a hooded upper lip and a three-lobed lower lip; the petals are pink to purplish in color. Flowers have four stamens, two long and two short, and a superior ovary with a bifid style. The fruit is a schizocarp that splits into four nutlets. Motherwort is an introduced species native to Europe and parts of Asia. In South Dakota, it is found scattered in disturbed habitats, roadsides, and fields throughout the state.

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  Lamiaceae : Mentha arvensis

  R. Neil Reese

  Mentha arvensis is an aromatic, perennial, rhizomatous herb with square, simple to branched, ascending to erect stems growing from 30-90 cm tall. The stems are usually hairy to nearly smooth with rings of hairs at the nodes. The simple, opposite leaf blades are lanceolate to ovate, 2.5-12 cm long and 5-40 mm wide, slightly small toward the top, with the upper surface generally without hairs and the lower surface with hairs along the veins. The margins are toothed with hairs along the edges and the petioles are 3-15 mm long. The inflorescence consist of paired 8-30 flowered cymes in the axils of leafy bracts. Each flower with a pedicel 1-3 mm long. The 5-lobed hairy calyx is tubular to bell-shaped, 2.5 -3.3 mm long, with teeth about ¼ length of the tube. The weakly bilabiate corolla is whitish to lavender in color, 4.5-6.5 mm long. The 4 stamens and the style are exerted from the corolla by 1-2 mm. the fruit are 4 nutlets. Field mint blooms from July into September in moist shaded sites, streambanks, lake shores and marshes throughout South Dakota.

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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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  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 : 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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  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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  Moraceae: Morus alba

  R. Neil Reese

  Morus alba is a deciduous tree growing 10 to 20 meters tall, with a broad, spreading crown and rough, furrowed grayish-brown bark. Leaves are alternate, simple, and variable in shape—ovate to deeply lobed—measuring 5 to 15 cm long and 4 to 12 cm wide, with serrated or wavy margins and petioles 1 to 3 cm long. Leaf surface can be smooth or slightly hairy, sometimes variegated. . The species is dioecious or sometimes monoecious, with small greenish unisexual flowers arranged in catkin-like inflorescences. Male flowers occur in slender cylindrical catkins 3 to 7 cm long and 0.5 to 1 cm wide, each flower apetalous with usually 4 stamens bearing 2 to 3 mm long filaments and longitudinally dehiscent anthers that release pollen. Female flowers are grouped in shorter, compact catkins 1.5 to 4 cm long and 0.5 to 1 cm wide, consisting mainly of a single superior ovary with one locule and ovule, a short cylindrical style 1 to 2 mm long, and a bifid, papillose stigma. Both flower types have a perianth of 4 to 6 small, scale-like tepals under 1 mm long protecting reproductive parts. The fruit is a multiple fruit (syncarp), 2 to 3 cm long, resembling a blackberry and ripening to white, pink, red, or dark purple, composed of numerous small druplets. The fruits are edible and sweet. Native to China, White mulberry has been widely introduced worldwide, and has adapted well to the region’s climate. Its presence is most notable in the eastern and central parts of the state where human settlement and cultivation have introduced it widely.

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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.