SABATIA (Family: Gentianaceae)

Sabatia campanulata (Linnaeus) Torrey - Slender Marsh-pink. 2n = 34.

Pond margins.

SABATIA CAMPESTRIS Nuttall - Texas-star. 2n = 26.

Waste places, fields. From farther west and south.

Sabatia dodecandra (Linnaeus) Britton, Sterns & Poggenburg - Large Marsh-pink. 2n = 38.

Salt marshes.

Sabatia kennedyana Fernald - Plymouth Gentian. 2n = 40.

Sandy and sphagnous shores of freshwater ponds.

Sabatia stellaris Pursh - Salt-marsh Pink. 2n = 36.

Salt or brackish marshes and meadows, brackish pond shores.

Sabatia hybrid

Sabatia campanulata (Linnaeus) Torrey X S. kennedyana Fernald - .

SAGINA (Family: Caryophyllaceae)

Sagina decumbens (Elliott) Torrey & A. Gray subsp. decumbens - Trailing Pearlwort. 2n = 22, 36.

Dry, sandy soil, roadsides, sidewalk cracks.

SAGINA JAPONICA (Swartz) Ohwi - Japanese Pearlwort. 2n = 46, 64.

Dryish, waste places. From eastern Asia.

SAGINA MAXIMA A. Gray subsp. MAXIMA - Beach Pearlwort. 2n = 22, 44, 66.

Rocky shores, gravelly beaches. From farther west.

SAGINA NODOSA (Linnaeus) Fenzl subsp. NODOSA - Knotted Pearlwort. 2n = (22), (44), 56.

Moist, coastal ledges and rock crevices. From Europe. [S. NODOSA var. PUBESCENS (Mertens & W.D.J. Koch) W.D.J. Koch]

Sagina nodosa (Linnaeus) Fenzl subsp. borealis G.E. Crow - Knotted Pearlwort. 2n = 56.

Moist, coastal ledges and rock crevices.

SAGINA PROCUMBENS Linnaeus - Matted Pearlwort. 2n = 22.

Moist, gravelly or sandy roadsides, sidewalk cracks, rocky or sandy shores, sea cliffs. From Europe.

SAGITTARIA (Family: Alismataceae)

Sagittaria australis (J.G. Smith) Small - Appalachian Arrowhead. 2n = 22.

Slightly basic waters of gravelly sandbars.

Sagittaria cuneata E. Sheldon - Wapato. 2n = 22.

Alkaline waters of muddy shores and shallow water of rivers.   NHA herbarium image

Sagittaria engelmanniana J.G. Smith - . 2n = 22.

Acidic waters of shores, marshes, and bogs.   GH herbarium image

Sagittaria filiformis J.G. Smith - . 2n = 22.

Deep water of streams and in rapids. [S. subulata (Linnaeus) Buchenau var. gracillima (S. Watson) J.G. Smith]   NEBC herbarium image

Sagittaria graminea Michaux subsp. graminea - . 2n = 22.

Muddy or sandy shores, shallow water. [S. eatonii J.G. Smith]   CONN herbarium image

Sagittaria latifolia Willdenow - . 2n = 22.

Muddy shores, ditches, bogs. [S. latifolia var. obtusa (Engelmann) Wiegand]   CONN herbarium image

Sagittaria montevidensis Chamisso & Schlechtendahl subsp. spongiosa (Engelmann) Bogin - . 2n = 22.

Tidal mud flats of estuaries and salt marshes. [S. spathulata (J.G. Smith) Buchenau; Lophotocarpus spongiosus (Engelmann) J.G. Smith]   CONN herbarium image

Sagittaria rigida Pursh - . 2n = 22.

Alkaline or brackish shores and shallow water.   CONN herbarium image

Sagittaria subulata (Linnaeus) Buchenau - . 2n = 22.

Tidal mud.   CONN herbarium image

Sagittaria teres S. Watson - . 2n = 22.

Acid, sandy pond shores.   CONN herbarium image

SALICORNIA (Family: Amaranthaceae)

Salicornia bigelovii Torrey - Dwarf Saltwort. 2n = 36.

Salt marshes.

Salicornia depressa Standley - Samphire. 2n = 36.

Salt marshes. [S. europaea Linnaeus var. europaea - misapplied; S. europaea Linnaeus var. simplex (Pursh) Fernald]

Salicornia maritima S.L. Wolff & Jeffries - Slender Glasswort. 2n = 18.

Salt marshes, sea shores. [S. prostrata misapplied; S. europaea Linnaeus var. prostrata misapplied]

SALIX (Family: Salicaceae)

SALIX ALBA Linnaeus - White Willow. 2n = 76.

Low moist ground, along streams, shores, roadsides. From Eurasia. [S. ALBA var. CALVA G. Meyer; S. ALBA var. VITELLINA (Linnaeus) Stokes]

Salix amygdaloides Andersson - Peach-leaved Willow. 2n = 38.

Lake shores, low woods.

Salix arctophila Cockerell ex A. Heller - Northern Willow. 2n = 76.

Alpine meadows.

Salix argyrocarpa Andersson - Labrador Willow. 2n = 76.

Alpine or subalpine meadows.

SALIX ATROCINEREA Brotero - Rusty Willow. 2n = (74), 76.

Marshes, wooded wetlands. From Europe.

SALIX AURITA Linnaeus - Eared Willow. 2n = 38, 76.

Waste places. From Eurasia.

Salix bebbiana Sargent - Bebb Willow. 2n = 38.

Damp thickets, springy places.

Salix candida Flüggé ex Willdenow - Hoary Willow. 2n = 38.

Calcareous bogs and swamps.

SALIX CAPREA Linnaeus - Goat Willow. 2n = 38, (51), (57), (76).

Thickets, roadsides. From Europe

SALIX CINEREA Linnaeus - Gray Willow. 2n = (44), 76.

Sandy or gravelly, freshwater shores, wet thickets, moist waste places. From Eurasia.

Salix discolor Muhlenberg - Pussy Willow. 2n = 76, 95, 114.

Damp thickets, freshwater shores, swamps. [S. discolor var. overi C.R. Ball]

SALIX ELAEAGNOS Scopoli - Olive Willow. 2n = 38.

Shores, rocky banks. From Europe. [S. INCANA Schrank]

Salix eriocephala Michaux - Wand Willow. 2n = 38, (44).

Low thickets, pond shores, streambanks, swamps. [S. cordata misapplied; S. cordata Muhlenberg var. abrasa Fernald; S. rigida Muhlenberg; S. rigida var. angustata (Pursh) Fernald]

Salix herbacea Linnaeus - Dwarf Willow. 2n = 38.

Mossy rocks in alpine areas.

Salix humilis Marshall var. humilis - Prairie Willow. 2n = 38, 76.

Dry thickets, openings, dry, mixed woods. [S. humilis var. hyporhysa Fernald; S. humilis var. keweenawensis Farwell]

Salix humilis Marshall var. tristis (Aiton) Griggs - Dwarf Prairie Willow. 2n = ?

Dry barrens, open woods, swampy areas in woods. [S. humilis var. microphylla (Andersson) Fernald; S. occidentalis Walter]

Salix interior Rowlee - Sandbar Willow. 2n = 38.

Sandy or silty alluvial soil, river sandbars, streambanks, shores. [S. interior var. exterior Fernald; S. exigua Nuttall subsp. interior (Rowlee) Cronquist]

Salix lucida Muhlenberg - Shining Willow. 2n = 76.

Low grounds, freshwater shores, swamps. [S. lucida var. angustifolia Andersson; S. lucida var. intonsa Fernald]

Salix myricoides Muhlenberg - Blue-leaf Willow. 2n = ?

River thickets, gravelly shores, usually in calcareous soil. [S. glaucophylloides Fernald]

SALIX MYRSINIFOLIA Salisbury - Dark-leaved Willow. 2n = 114.

Waste places, roadsides. From Eurasia.

Salix nigra Marshall - Black Willow. 2n = 38.

Streambanks, shores, rich, low, woods.

Salix pedicellaris Pursh - Bog Willow. 2n = 38, 57, 76.

Sphagnum bogs and swamps, sphagnous shores. [S. pedicellaris var. hypoglauca Fernald; S. pedicellaris var. tenuescens Fernald]

Salix pellita (Andersson) Bebb - Satin Willow. 2n = 38, 76.

Streambanks, shores, rich, thickets.

Salix petiolaris Smith - Slender Willow. 2n = 38.

Meadows, river thickets, low, moist openings in deciduous woods. [S. gracilis Andersson; S. gracilis var. textoris Fernald; S. X subsericea (Andersson) C.K. Schneider (pro species)]

Salix planifolia Pursh - Tea-leaved Willow. 2n = 57, 76.

Alpine, subalpine and boreal meadows, streambanks, wet thickets.

SALIX PURPUREA Linnaeus - Purple Osier. 2n = 38.

Low, wet ground. From Europe.

Salix pyrifolia Andersson - Balsam Willow. 2n = 38.

Bogs, swamps, damp thickets.

Salix sericea Marshall - Silky Willow. 2n = ?

River thickets, swamps. [S. coactilis Fernald]

Salix serissima (L.H. Bailey) Fernald - Autumn Willow. 2n = 76.

Calcareous marshes, bogs and swamps.

SALIX TRIANDRA Linnaeus - Almond Willow. 2n = 38 (44), (57), (88).

Streambanks, waste places. From Eurasia.

Salix uva-ursi Pursh - Bearberry Willow. 2n = 38.

Exposed, rocky, alpine areas.

SALIX VIMINALIS Linnaeus - Osier. 2n = 38.

Streambanks, roadsides, freshwater shores. From Europe.

Salix hybrids

SALIX ALBA Linnaeus X S. petiolaris Smith - .

Salix bebbiana Sargent X S. eriocephala Michaux - .

Salix bebbiana Sargent X S. humilis Marshall var. humilis - .

Salix bebbiana Sargent X S. petiolaris Smith - .

Salix X beschelii B. Boivin - .

[S. bebbiana Sargent X S. discolor Muhlenberg]

Salix candida Flüggé ex Willdenow X S. pellita (Andersson) Bebb - .

SALIX CINEREA Linnaeus X S. eriocephala Michaux - .

Salix X cryptodonta Fernald (pro species) - .

[S. bebbiana Sargent X S. candida Flüggé ex Willdenow]

Salix discolor Muhlenberg X S. eriocephala Michaux - .

Salix discolor Muhlenberg X S. humilis Marshall var. humilis - .

Salix discolor Muhlenberg X S. petiolaris Smith - .

Salix discolor Muhlenberg X S. pyrifolia Andersson - .

Salix eriocephala Michaux X S. lucida Muhlenberg - .

Salix eriocephala Michaux X S. myricoides Muhlenberg - .

Salix eriocephala Michaux X S. pedicellaris Pursh - .

Salix eriocephala Michaux X S. petiolaris Smith - .

Salix eriocephala Michaux X S. sericea Marshall - .

[S. X bebbii Gandoger - invalid name]

SALIX X FRAGILIS Linnaeus - Crack Willow.

[S. ALBA Linnaeus X S. EUXINA I.V. Belyaeva; S. X RUBENS Schrank (pro species)]

Salix X grayi C.K. Schneider - .

[S. argyrocarpa Andersson X S. planifolia Pursh]

Salix humilis Marshall var. humilis X S. petiolaris Smith - .

Salix humilis Marshall var. humilis X S. sericea Marshall - .

Salix humilis Marshall var. tristis (Aiton) Griggs X S. petiolaris Smith - .

Salix X jesupii Fernald - .

[S. ALBA Linnaeus X S. lucida Muhlenberg]

Salix lucida Muhlenberg X S. serissima (L.H. Bailey) Fernald - .

SALIX X MEYERIANA Rostkovius ex Willdenow - .

[S. PENTANDRAA Linnaeus X S. EUXINA I.V. Belyaeva; S. PENTANDRA misapplied]

Salix X peasei Fernald (pro species) - .

[S. herbacea Linnaeus X S. uva-ursi Pursh]

SALIX X PENDULINA Wenderoth - Weeping Willow.

[S. BABYLONICA Linnaeus X S. EUXINA I.V. Belyaeva; S. BABYLONICA misapplied]

Salix petiolaris Smith X S. sericea Marshall - .

Salix X rubella Bebb ex C.K. Schneider - .

[S. candida Flüggé ex Willdenow X S. eriocephala Michaux]

SALIX X SEPULCRALIS Simonkai - Weeping Willow.

[S. ALBA Linnaeus X S. BABYLONICA Linnaeus; S. BABYLONICA misapplied]

SALIX X SMITHIANA Willdenow (pro species) - .

[S. CAPREA Linnaeus X S. VIMINALIS Linnaeus; S. X SERICANS Tausch ex A. Kerner]

SALPIGLOSSIS (Family: Solanaceae)

SALPIGLOSSIS SINUATA Ruiz & Pavón - Painted-tongue. 2n = 44.

Waste places. From Chile.

SALSOLA (Family: Amaranthaceae)

SALSOLA COLLINA Pallas - Slender Russian Thistle. 2n = 18.

Waste places, roadsides, fields. From Eurasia.

SALSOLA KALI Linnaeus subsp. KALI - Common Saltwort. 2n = (30), 36, (54).

Sea beaches. From Europe.

SALSOLA KALI Linnaeus subsp. PONTICA (Pallas) Mosyakin - Prickly Russian Thistle. 2n = 18.

Sea beaches. From Eurasia, northern Africa. [S. KALI var. CAROLINIANA (Walter) Nuttall; S. CAROLINIANA Walter]

SALSOLA TRAGUS Linnaeus - Russian Thistle. 2n = (18), 36.

Sandy shores, roadsides, waste places, fields. From Eurasia. [S. IBERICA (Sennen & Pau) Botschantzev ex Czerepanov; S. KALI Linnaeus var. TENUIFOLIA Tausch; S. PESTIFER A. Nelson]

SALVIA (Family: Lamiaceae)

SALVIA AZUREA Michaux ex Vahl var. GRANDIFLORA Bentham - Blue Sage. 2n = 20.

Waste places, sidewalks. From farther west. [S. PITCHERI Torrey ex Bentham]

SALVIA FARINACEA Bentham - Mealy-cup Sage. 2n = 18, (20).

Roadsides. From south central United States.

Salvia lyrata Linnaeus - Cancerweed. 2n = 36.

Meadows.

SALVIA OFFICINALIS Linnaeus - Garden Sage. 2n = 14, (16).

Roadsides, fields, fencerows, river thickets. From southeastern Europe.

SALVIA PRATENSIS Linnaeus - Meadow Sage. 2n = (16), 18, (20), (32).

Waste places, fields, grassy hillsides, roadsides. From Europe.

SALVIA SCLAREA Linnaeus - Clary Sage. 2n = 22.

Waste places, fencerows. From Eurasia.

SALVIA SPLENDENS Sellow ex Nees - Scarlet Sage. 2n = (16), (20), (32), 44.

Waste places. From Brazil.

SALVIA TILIIFOLIA Vahl - . 2n = 22.

Waste places. From Mexico, Central and South America.

SALVIA VERTICILLATA Linnaeus - Lilac Sage. 2n = 16, (32).

Fields, meadows, waste places, roadsides. From Eurasia.

Salvia hybrid

SALVIA X SYLVESTRIS Linnaeus (pro species) - .

[S. NEMOROSA Linnaeus X S. PRATENSIS Linnaeus; S. NEMOROSA misapplied]

SALVINIA (Family: Salviniaceae)

SALVINIA MINIMA Baker - Floating Fern. 2n = 36, 54.

On still waters of ponds or slow streams. From Europe and Asia. [S. natans misapplied; S. rotundifolia misapplied] NEBC herbarium image

SAMBUCUS (Family: Adoxaceae)

Sambucus canadensis Linnaeus - Common Elder. 2n = 36.

Swamps, wet woods, damp roadsides, moist soil. [S. nigra Linnaeus susp. canadensis (Linnaeus) Bolli]

SAMBUCUS EBULUS Linnaeus - Danewort. 2n = (32), 36.

Roadsides. From Eurasia, northern Africa.

SAMBUCUS NIGRA Linnaeus - European Elder. 2n = 36.

Waste ground. From Eurasia, northern Africa.

Sambucus racemosa Linnaeus - Red-berried Elder. 2n = 36, (38), (42).

Rich woods, openings, often rocky. [S. pubens Michaux; S. racemosa Linnaeus subsp. pubens (Michaux) Hultén]

SAMOLUS (Family: Primulaceae)

Samolus parviflorus Rafinesque - Seaside Brookweed. 2n = 26.

Tidal shores, wet places. [S. floribundus Kunth]

SANGUINARIA (Family: Papaveraceae)

Sanguinaria canadensis Linnaeus - Bloodroot. 2n = 18.

Rich woods.

SANGUISORBA (Family: Rosaceae)

Sanguisorba canadensis Linnaeus - American Burnet. 2n = 28, 56.

Meadows, swamps, low ground, sphagnous soils.

SANGUISORBA OFFICINALIS Linnaeus - Great Burnet. 2n = (14), 28, (42), 56.

Roadsides, fields, thickets. From Eurasia, northwestern North America.

SANICULA (Family: Apiaceae)

Sanicula canadensis Linnaeus var. canadensis - . 2n = 16.

Rich woodlands.

Sanicula canadensis Linnaeus var. grandis - . 2n = ?

Rich woodlands.

Sanicula marilandica Linnaeus - Black Snakeroot. 2n = 16.

Open woodlands, thickets, often in dry, rich, rocky soil.

Sanicula odorata (Rafinesque) Pryer & Phillippe - . 2n = 16.

Rich woodlands. [S. gregaria E.P. Bicknell]

Sanicula trifoliata E.P. Bicknell - . 2n = ?

Rich woodlands.

SANTOLINA (Family: Asteraceae)

SANTOLINA CHAMAECYPARISSUS Linnaeus - Lavender-cotton. 2n = 18, (36), (45).

Dry, sandy banks, roadsides, thin, pine woods. From Europe.

SAPONARIA (Family: Caryophyllaceae)

SAPONARIA OCYMOIDES Linnaeus - Rock Soapwort. 2n = 28.

Waste places. From Europe.

SAPONARIA OFFICINALIS Linnaeus - Bouncing-bet. 2n = 28.

Roadsides, waste places, fields. From Eurasia.

SAPONARIA PUMILIO Boissier - Pygmy Pink. 2n = ?

Ledges. From Europe. [SILENE PUMILIO (Linnaeus) Wulfen]

SARCOCORNIA (Family: Amaranthaceae)

Sarcocornia ambigua (Michaux) M.A. Alonso & M.B. Crespo - Woody Glasswort. 2n = 18.

Sea beaches, tidal flats, salt marshes. [S. pacifica misapplied; Salicornia virginica misapplied]

SARRACENIA (Family: Sarraceniaceae)

SARRACENIA FLAVA Linnaeus - Trumpets. 2n = 26.

Floating Sphagnum mats. From farther south.

Sarracenia purpurea Linnaeus subsp. purpurea - Common Pitcher-plant. 2n = 26.

Peaty soil of bogs, swamps and pond margins.

SASSAFRAS (Family: Lauraceae)

Sassafras albidum (Nuttall) Nees - Sassafras. 2n = 48.

Woods, thickets, woodland borders. [S. albidum var. molle (Rafinesque) Fernald]

SATUREJA (Family: Lamiaceae)

SATUREJA HORTENSIS Linnaeus - Summer Savory. 2n = (45), 48.

Waste places, fields, railroads, roadsides, gravelly banks. From Eurasia.

SAURURUS (Family: Saururaceae)

Saururus cernuus Hooker & Arnott - Lizard's-tail. 2n = 22.

Stream borders, shallow water, swamps, marshes.

SAXIFRAGA (Family: Saxifragaceae)

Saxifraga aizoides Linnaeus - Yellow Mountain Saxifrage. 2n = 26.

Calcareous cliffs.

Saxifraga cernua Linnaeus - Nodding Saxifrage. 2n = 24, 36, 48, 50, 52, 56, 60, 62, 64, 70, 72.

Wet ledges at high altitude.

Saxifraga oppositifolia Linnaeus subsp. oppositifolia - Purple Mountain Saxifrage. 2n = 26, (39), (48), (52).

Calcareous cliffs.

Saxifraga paniculata Miller - White Mountain Saxifrage. 2n = 28.

Rocky ledges, often calcareous. [S. aizoon Jacquin var. neogaea Butters]

Saxifraga rivularis Linnaeus subsp. rivularis - Alpine Brook Saxifrage. 2n = (26), (48), 52, (56).

Wet, mossy, alpine areas.

SCABIOSA (Family: Caprifoliaceae)

SCABIOSA OCHROLEUCA Linnaeus - Cream Scabious. 2n = 16, (24).

Waste places, gravel pits. From Eurasia.

SCANDIX (Family: Apiaceae)

SCANDIX PECTEN-VENERIS Linnaeus - Shepherd’s-needle. 2n = (16), 26, (28), (34).

Waste places. From Eurasia, northern Africa.

SCHENKIA (Family: Gentianaceae)

SCHENKIA SPICATA (Linnaeus) G. Mansion - . 2n = 22.

Salt marshes. From Mediterranean region, western Russia, southwestern Asia. [CENTAURIUM SPICATUM (Linnaeus) Fritsch]

SCHEUCHZERIA (Family: Scheuchzeriaceae)

Scheuchzeria palustris Linnaeus - . 2n = 22.

Sphagnum bogs. [S. palustris var. americana Fernald]

SCHIZACHNE (Family: Poaceae)

Schizachne purpurascens (Torrey) Swallen subsp. purpurascens - False Melic. 2n = 20.

Rich woods.

SCHIZACHYRIUM (Family: Poaceae)

Schizachyrium scoparium (Michaux) Nash var. scoparium - Little Bluestem. 2n = 40.

Dry soil, old fields, open woods. [Andropogon scoparius Michaux var. scoparius; A. scoparius var. frequens F.T. Hubbard; A. scoparius var. septentrionalis Fernald & Griscom]

Schizachyrium scoparium (Michaux) Nash var. littorale (Nash) Gould - . 2n = ?

Upper borders of sea beaches, dunes. [Andropogon littoralis Nash; A. scoparius Michaux var. ducis Fernald & Griscom; A. scoparius var. littoralis (Nash) Hitchcock; S. littorale (Nash) E.P. Bicknell]

SCHOENOPLECTIELLA (Family: Cyperaceae)

Schoenoplectiella hallii (A. Gray) Lye - . 2n = 22.

Sandy or sphagnous pond shores. [Schoenoplectus hallii (A. Gray) S.G. Smith; Scirpus hallii A. Gray; S. supinus Linnaeus var. hallii (A. Gray) A. Gray]

SCHOENOPLECTIELLA MUCRONATA (Linnaeus) J. Jung & H.K. Choi - . 2n = (38), (40). (42), 44.

Pond shores. From Eurasia, Africa, Australia. [SCHOENOPLECTUS MUCRONATUS (Linnaeus) Palla; SCIRPUS MUCRONATUS Linnaeus]

Schoenoplectiella purshianus (Fernald) Lye var. purshianus - . 2n = 36, 38.

Freshwater shores, usually in sandy soil. [Schoenoplectus purshianus (Fernald) M.T. Strong var. purshianus; Scirpus purshianus Fernald]

Schoenoplectiella purshianus (Fernald) Lye var. williamsii (Fernald) Hayasaka - . 2n = 38.

Sandy lake shores. [Schoenoplectus purshianus (Fernald) M.T. Strong var. williamsii S.G. Smith; Scirpus debilis Lamarck var. williamsii Fernald; S. purshianus Fernald forma williamsii (Fernald) Fernald]

Schoenoplectiella smithii (A. Gray) Hayasaka var. smithii - . 2n = (18), 40

Sandy or muddy shores. [Schoenoplectus smithii (A. Gray) Soják var. smithii; Scirpus smithii A. Gray]

Schoenoplectiella smithii (A. Gray) Hayasaka var. leviseta (Fassett) Hayasaka - . 2n = 40.

Coastal, freshwater tidal flats. [Schoenoplectus smithii (A. Gray) Soják var. levisetus (Fassett) S.G. Smith; Scirpus smithii A. Gray forma levisetus (Fassett) Fernald] [This taxon is not mapped since it is inadequately separated from the typical variety in collections.]

Schoenoplectiella smithii (A. Gray) Hayasaka var. setosa (Fernald) Hayasaka - . 2n = 40.

Freshwater, sandy or muddy shores. [Schoenoplectus smithii (A. Gray) Soják var. setosus (Fernald) S.G. Smith; Scirpus smithii A. Gray forma setosus Fernald] [This taxon is not mapped since it is inadequately separated from the typical variety in collections.]

SCHOENOPLECTUS (Family: Cyperaceae)

Schoenoplectus acutus (Muhlenberg ex Bigelow) Á. Löve & D. Löve var. acutus Hard-stem Bulrush - . 2n = 36, 38, 40, 42.

Shores and marshes. [Scirpus acutus Muhlenberg ex Bigelow]

Schoenoplectus americanus (Persoon) Volkart ex Schinz & R. Keller Sword-grass - . 2n = (38), (76), 78.

Shores and marshes. [Scirpus americanus Persoon; S. olneyi A. Gray]

Schoenoplectus heterochaetus (Chase) Soják Slender Bulrush - . 2n = 36, 38.

Calcareous or basic shores and marshes. [Scirpus heterochaetus Chase]

Schoenoplectus pungens (Vahl) Palla var. pungens Chair-maker's Bulrush - . 2n = 74, 78.

Shores and marshes. [Scirpus pungens Vahl]

Schoenoplectus subterminalis (Torrey) Soják Water Bulrush - . 2n = 74.

Shores and Sphagnum bogs. [Scirpus subterminalis Torrey]

Schoenoplectus tabernaemontani (C.C. Gmelin) Palla Great Bulrush - . 2n = (38), (40), 42.

In shallow water of shores and marshes. [Scirpus validus Vahl; S. validus Vahl var. creber Fernald]

Schoenoplectus torreyi (Olney) Palla - . 2n = 42, 70.

Shores and marshes. [Scirpus torreyi Olney]

Schoenoplectus hybrids

Schoenoplectus acutus (Muhlenberg ex Bigelow) Á. Löve & D. Löve X S. tabernaemontani (C.C. Gmelin) Palla

Schoenoplectus X contortus (Eames) S.G. Smith - .

[S. americanus (Persoon) Volkart ex Schinz & R. Keller X S. pungens (Vahl) Palla]

Schoenoplectus X oblongus (T. Koyama) Soják - .

[S. acutus (Muhlenberg ex Bigelow) Á. Löve & D. Löve X S. heterochaetus (Chase) Soják]

Schoenoplectus X steinmetzii (Fernald) S.G. Smith - .

[S. heterochaetus (Chase) Soják X S. tabernaemontani (C.C. Gmelin) Palla]

SCHWALBEA (Family: Orobanchaceae)

Schwalbea americana Linnaeus - Chaffseed. 2n = 32, 36.

Pine-oak woods, clearings, sandy fields.

SCILLA (Family: Asparagaceae)

SCILLA SIBERICA Andrews - . 2n = 12, 18, (24), (30).

Roadsides, pastures. From Eurasia.   NEBC herbarium image

SCIRPUS (Family: Cyperaceae)

Scirpus ancistrochaetus Schuyler - . 2n = 54.

Wet depressions, bogs.

Scirpus atrocinctus Fernald - . 2n = 68.

Meadows and swamps.

Scirpus atrovirens Willdenow - . 2n = (50), 56, (62).

Marshes, meadows, bogs.

Scirpus cyperinus (Linnaeus) Kunth Common Wool-grass - . 2n = (60), (64), 66, (68), (70).

Meadows, swamps and ditches.  [S. cyperinus var. pelius Fernald; S. rubricosus Fernald]

Scirpus expansus Fernald Woodland Bulrush - . 2n = 64.

Marshes, meadows and springy spots.

Scirpus georgianus R.M. Harper - . 2n = 48, 50, 52, 54.

Marshes, meadows and ditches.  [S. atrovirens Willdenow var. georgianus (R.M. Harper) Fernald]

Scirpus hattorianus Makino - . 2n = 56.

Marshes, meadows and ditches.  [S. atrovirens misapplied; S. georgianus misapplied]

Scirpus longii Fernald - . 2n = 66, 68.

Freshwater marshes, meadows.

Scirpus microcarpus J. Presl & C. Presl - . 2n = 62, 64, 66.

Damp, open soil, marshes, meadows, often along rivers. [S. rubrotinctus Fernald]

SCIRPUS PALLIDUS (Britton) Fernald - . 2n = 56.

Marshes, ditches and other low ground. From farther west.

Scirpus pedicellatus Fernald - . 2n = 68, (136).

Alluvial thickets, shores.  [S. pedicellatus var. pullus Fernald]

Scirpus pendulus Muhlenberg - . 2n = 40.

Meadows, marshes, ditches, often in calcareous soil.  [S. lineatus misapplied]

Scirpus polyphyllus Vahl - . 2n = 58.

Swamps and woods along streams.

Scirpus hybrids

Scirpus ancistrochaetus Schuyler X S. hattorianus Makino

Scirpus atrocinctus Fernald X S. hattorianus Makino

Scirpus atrovirens Willdenow X S. polyphyllus Vahl

Scirpus expansus Fernald X S. microcarpus J. Presl & C. Presl

Scirpus X peckii Britton (pro species) - .

[This name is said to have been applied to various hybrids of S. hattorianus Makino and S. atrocinctus Fernald or S. pedicellatus Fernald.]

SCLERANTHUS (Family: Caryophyllaceae)

SCLERANTHUS ANNUUS Linnaeus subsp. ANNUUS - Annual Knawel. 2n = (22), 44.

Roadsides, waste places, dry, sandy soil. From Eurasia, northern Africa.

SCLERANTHUS PERENNIS Linnaeus subsp. PERENNIS - Perennial Knawel. 2n = 22, 44.

Roadsides, dry, sandy soil. From Eurasia.

SCLERIA (Family: Cyperaceae)

Scleria pauciflora Muhlenberg ex Willdenow var. pauciflora - . 2n = ?

Meadows and moist woods.

Scleria pauciflora Muhlenberg ex Willdenow var. caroliniana Alph. Wood - . 2n = ?

Moist grasslands.

Scleria reticularis Michaux - . 2n = ?

Sandy pond shores.

Scleria triglomerata Michaux - . 2n = ?

Meadows and dry, open woods. [S. nitida Willdenow ex Kunth]

Scleria verticillata Muhlenberg ex Willdenow - . 2n = ?

Calcareous bogs and shores.

SCLEROLEPIS (Family: Asteraceae)

Sclerolepis uniflora (Walter) Britton, Sterns, & Poggenberg - Pink Bogbutton. 2n = 30, ca. 60.

Sandy or sphagnous shores or shallow water of ponds and lakes.

SCORPIURUS (Family: Fabaceae)

SCORPIURUS MURICATUS Linnaeus - Caterpillar-plant. 2n = 28.

Wool waste. From the Mediterranean.

SCORZONEROIDES (Family: Asteraceae)

SCORZONEROIDES AUTUMNALIS (Linnaeus) Moench - Fall Dandelion. 2n = 12, (14), (16), (32).

Fields, meadows, roadsides. From Eurasia. [LEONTODON AUTUMNALIS Linnaeus var. AUTUMNALIS; L. AUTUMNALIS var. PRATENSIS Koch]

SCROPHULARIA (Family: Scrophulariaceae)

Scrophularia lanceolata Pursh - . 2n = 96.

Fields, thickets, woodland margins, open woods, roadsides.

Scrophularia marilandica Linnaeus - Carpenter’s-square. 2n = ca. 86.

Woods, thickets, roadsides, streambanks.

SCROPHULARIA NODOSA Linnaeus - European Figwort. 2n = 36.

Thickets, roadsides, waste places. From Eurasia.

SCUTELLARIA (Family: Lamiaceae)

Scutellaria galericulata Linnaeus - Marsh Skullcap. 2n = (28), 30, (31), 32.

Swamps, shores, meadows, marshes. [S. epilobiifolia A. Hamilton]

Scutellaria integrifolia Linnaeus - . 2n = 32.

Fields, meadows.

Scutellaria lateriflora Linnaeus var. lateriflora - Mad-dog Skullcap. 2n = 80, 88.

Wet woodlands, shores, meadows, alluvial thickets, marshes.

Scutellaria parvula Michaux var. parvula - . 2n = 20.

Rocky outcrops of shores and fields.

Scutellaria parvula Michaux var. missouriensis (Torrey) Goodman & C.A. Lawson - . 2n = 20.

Rocky outcrops of shores, fields, ridges, hills, and open woodlands. [S. parvula var. leonardi (Epling) Fernald]

Scutellaria hybrid

Scutellaria X churchilliana Fernald (pro species) - .

[S. galericulata Linnaeus X S. lateriflora Linnaeus]

SECALE (Family: Poaceae)

SECALE CEREALE Linnaeus - Rye. 2n = (7), 14, (16), (18), (21), (27), (28), (29).

Waste places, roadsides. From Eurasia.

SECURIGERA (Family: Fabaceae)

SECURIGERA VARIA (Linnaeus) Lassen - Crown-vetch. 2n = (16), 24.

Roadsides, fields, waste places. From Eurasia. [CORONILLA VARIA Linnaeus]

SEDUM (Family: Crassulaceae)

SEDUM ACRE Linnaeus - Mossy Stonecrop. 2n = (16), (24), 40, (48), (56), 60, 80, (100), (120).

Rock outcrops, rock walls, dry, open places. From Europe and Greenland.

SEDUM ALBUM Linnaeus - White Stonecrop. 2n = (18), 34, (36), (51), (64), 68, (85), (102), (136).

Rocky soil. From Europe.

SEDUM HISPANICUM Linnaeus - Spanish Stonecrop. 2n = 14, (20), (28), (30), (40), (42).

Roadsides, rocky fields. From Eurasia.

SEDUM OCHROLEUCUM Chaix - . 2n = 34, 68, (51), (85), (102).

Roadsides, rocky fields, waste places. From Europe. [S. ANOPETALUM de Candolle]

SEDUM RUPESTRE Linnaeus - Jenny's Stonecrop. 2n = (56), (88), (102), (108), 112, (120), (122), (140), (153), (168).

Roadsides, waste places. From Europe. [S. REFLEXUM Linnaeus]

SEDUM SARMENTOSUM Bunge - Stringy Stonecrop. 2n = 58, 72.

Roadsides, waste places. From China.

SEDUM SEXANGULARE Linnaeus - Tasteless Stonecrop. 2n = (72), 74, (108), (111), (148), (185).

Roadsides, waste places. From Europe.

SEDUM TERNATUM Michaux - Wild Stonecrop. 2n = 16, 24, 32, 48.

Damp roadsides. From farther south or west.

SELAGINELLA (Family: Selaginellaceae)

Selaginella apoda (Linnaeus) C. Morren - Meadow Spikemoss. 2n = 18.

Meadows, stream banks, wet rocks, often in circumneutral soils. CONN herbarium image

Selaginella eclipes W.R. Buck - . 2n = ?

Wet hillsides, stream banks. CONN herbarium image

Selaginella rupestris (Linnaeus) Spring - Rock Spikemoss. 2n = 18.

Exposed, dry rocks or packed sands. CONN herbarium image

Selaginella selaginoides (Linnaeus) Schrank & Martius - Northern Spikemoss. 2n = 18.

Damp shores and banks, bogs, springs, often calcareous. CONN herbarium image

SELINUM (Family: Apiaceae)

SELINUM CARVIFOLIA (Linnaeus) Linnaeus - 2n = 22.

Damp roadsides, ditches. From Eurasia.

SEMPERVIVUM (Family: Crassulaceae)

SEMPERVIVUM TECTORUM Linnaeus - Hens-and-chickens. 2n = 36, 40, 72.

Rocky outcrops, ledges, stone walls, other rocky sites. From Europe.

SENECIO (Family: Asteraceae)

SENECIO EREMOPHILUS Richardson var. MACDOUGALII (A. Heller) Cronquist - . 2n = 40.

From farther west. [S. MACDOUGALII A. Heller]

Senecio suaveolens (Linnaeus) Elliott - . 2n = (36), 40.

Stream banks, thickets, rich woods. [Cacalia suaveolens Linnaeus; Hasteola suaveolens (Linnaeus) Pojarkova]

SENECIO SYLVATICUS Linnaeus - Heath Groundsel. 2n = 40.

Cliff crevices, sandy beaches, gravelly seashores, waste places, roadsides. From Europe.

SENECIO VISCOSUS Linnaeus - . 2n = (20), (24), 40.

Waste places. From Eurasia.

SENECIO VULGARIS Linnaeus - Common Groundsel. 2n = (20), (27), (38), 40.

Roadsides, waste places. From Eurasia, northern Africa.

SENNA (Family: Fabaceae)

Senna hebecarpa (Fernald) H.S. Irwin & Barneby - Wild Senna. 2n = ?

Streambanks, thickets, roadsides, fields. [Cassia hebecarpa Fernald; C. marilandica misapplied]

SENNA OBTUSIFOLIA (Linnaeus) H.S. Irwin & Barneby - Java-bean. 2n = (24), 26, 28, (52), (56).

Waste places. From farther south.

SERICOCARPUS (Family: Asteraceae)

Sericocarpus asteroides (Linnaeus) Britton, Sterns, & Poggenberg - Toothed White-top Aster. 2n = 18.

Dry woods, clearings, and fields, roadsides. [Aster paternus Cronquist]

Sericocarpus linifolius (Linnaeus) Britton, Sterns, & Poggenberg - 2n = 18, (54).

Dry woods, clearings, and fields, roadsides. [Aster solidagineus Michaux]

SESAMUM (Family: Pedaliaceae)

SESAMUM INDICUM Linnaeus - Sesame. 2n = (18), 26, (52).

Waste places. Long cultivated, possibly from Africa or India. [S. ORIENTALE Linnaeus]

SESBANIA(Family: Fabaceae)

SESBANIA HERBACEA (Miller) McVaugh - . 2n = 12.

Waste places. From farther south. [S. EXALTATA (Rafinesque) Rydberg]

SESUVIUM (Family: Aizoaceae)

Sesuvium maritimum (Walter) Britton, Sterns, & Poggenberg - . 2n = ?

Pond shore behind coastal dune.

SETARIA (Family: Poaceae)

SETARIA FABERI R.A.W. Herrmann - . 2n = 36.

Roadsides, railroads, waste places, fields. From eastern Asia.

SETARIA ITALICA (Linnaeus) P. Beauvois - Foxtail Millet. 2n = 18, (36).

Cultivated land, waste places, roadsides. From the Old World.

Setaria parviflora (Poiret) Kerguélen var. parviflora - . 2n = 36, 72.

Salt marsh borders, hillsides, waste places. [S. geniculata misapplied]

SETARIA PUMILA (Poiret) Roemer & Schultes - Yellow Foxtail. 2n = (18), 36, (54), (72).

Dry sandy soil, roadsides, waste places. From Europe. [S. GLAUCA misapplied; S. LUTESCENS (Stuntz) F.T. Hubbard]

SETARIA VERTICILLATA (Linnaeus) P. Beauvois - Bur Foxtail. 2n = 18, 36, 54, (72), (108).

Waste places. From Eurasia.

SETARIA VIRIDIS (Linnaeus) P. Beauvois var. VIRIDIS - Green Foxtail. 2n = 18, (36).

Fields, roadsides, railroads, waste places. From Europe. [S. VIRIDIS var. BREVISETA (Döll) Hitchcock; S. VIRIDIS var. WEINMANNII (Roemer & Schultes) Heynhold]

SHEPHERDIA (Family: Elaeagnaceae)

Shepherdia canadensis (Linnaeus) Nuttall - Soapberry. 2n = 22.

Calcareous ledges and rocky outcrops along shores of rivers and lakes.

SHERARDIA (Family: Rubiaceae)

SHERARDIA ARVENSIS Linnaeus - Field-Madder. 2n = 22.

Fields, waste places. From Eurasia. [GALIUM SHERARDIA E.H.L. Krause]

SIBBALDIA (Family: Rosaceae)

Sibbaldia procumbens Linnaeus - 2n = 14.

Headwalls of alpine ravines.

SIBBALDIOPSIS (Family: Rosaceae)

Sibbaldiopsis tridentata (Aiton) Rydberg - Three-toothed Cinquefoil. 2n = 28.

Dry, open, rocky, gravelly or sandy, sterile soil, clefts in ledges, often at high altitudes. [Potentilla tridentata Aiton]

SICYOS (Family: Cucurbitaceae)

Sicyos angulatus Linnaeus - Bur-cucumber. 2n = 24.

Waste places. From eastern Mediterranean region, southwestern Asia.

SIDA (Family: Malvaceae)

SIDA HERMAPHRODITA (Linnaeus) Rusby - Virginia Mallow. 2n = ?

Waste places, fields. From farther south.

SIDA SPINOSA Linnaeus - Prickly Mallow. 2n = 14, 28.

Waste places, wool waste, fields. From tropical Americas, tropical Africa, tropical Asia.

SIDERITIS (Family: Lamiaceae)

SIDERITIS MONTANA Linnaeus - . 2n = 16, (18), (28), 32.

Waste places, dry, open ground. From Eurasia, northwestern Africa.

SIGESBECKIA (Family: Asteraceae)

SIGESBECKIA JORULLENSIS Kunth - 2n = 30, (ca. 32).

Waste places. From Mexico, Central America, South America.

SILENE (Family: Caryophyllaceae)

Silene acaulis (Linnaeus) Jacquin - Moss Campion. 2n = (12), 24.

Alpine areas. [S. acaulis var. exscapa (Allioni) F.N. Williams]

Silene antirrhina Linnaeus - Sleepy Catchfly. 2n = 24.

Dry, sandy or rocky soil, railroads, fields, waste places.

SILENE ARMERIA Linnaeus - Garden Catchfly. 2n = 24.

Waste places, roadsides. From Eurasia. [ATOCION ARMERIA (Linnaeus) Rafinesque]

Silene caroliniana Walter subsp. pensylvanica (Michaux) R.T. Clausen - Wild Pink. 2n = 48.

Dry, often rocky, mainly deciduous woods and clearings.

SILENE CHALCEDONICA (Linnaeus) E.H.L. Krause - Maltese-cross. 2n = (18), 24, (48).

Roadsides, near habitations, waste places, open woods. From Eurasia. [LYCHNIS CHALCEDONICA Linnaeus]

SILENE CONICA Linnaeus subsp. CONICA - Sand Catchfly. 2n = (18), 20, (24).

Sandy fields and roadsides. From Eurasia.

SILENE CORONARIA (Linnaeus) Clairville - Mullein Pink. 2n = 24.

Waste places, roadsides, fields. From Europe. [LYCHNIS CORONARIA (Linnaeus) Desrousseaux]

SILENE CSEREII Baumgarten - Balkan Catchfly. 2n = 24.

Waste places, roadsides, railroads. From Europe.

SILENE DICHOTOMA Ehrhart subsp. DICHOTOMA - Forked Catchfly. 2n = 24, (48).

Fields, roadsides, waste places. From Europe.

SILENE DIOICA (Linnaeus) Clairville - Red Campion. 2n = 24.

Fields, roadsides, waste places. From Europe. [LYCHNIS DIOICA Linnaeus]

SILENE FLOS-CUCULI (Linnaeus) Clairville subsp. FLOS-CUCULI - Ragged Robin. 2n = 24.

Wet fields, meadows, roadside ditches. From Europe. [LYCHNIS FLOS-CUCULI Linnaeus]

SILENE GALLICA Linnaeus - French Catchfly. 2n = 24.

Waste places, roadsides. From Europe.

SILENE LATIFOLIA Poiret - White Campion. 2n = 24, (48).

Waste places, roadsides, field borders. From Eurasia. [S. LATIFOLIA subsp. ALBA (Miller) Greuter & Burdet; S. PRATENSIS (Rafinesque) Grenier & Godron; LYCHNIS ALBA Miller]

SILENE NIVEA (Nuttall) Muhlenberg ex Otth - Snowy Campion. 2n = 48.

Rich, shaded riverbanks. From farther west and south.

SILENE NOCTIFLORA Linnaeus - Night-flowering Catchfly. 2n = 24.

Arable land, waste places. From Europe.

SILENE NUTANS Linnaeus - Nottingham Catchfly. 2n = 24, (28).

Roadsides. From Eurasia.

SILENE PENDULA Linnaeus - Nodding Catchfly. 2n = 24.

Roadsides, fields. From Europe.

Silene stellata (Linnaeus) W.T. Aiton - Starry Campion. 2n = (34), 48.

Dry, open woods.

SILENE VISCARIA (Linnaeus) Jessen subsp. VISCARIA - German Catchfly. 2n = 24.

Roadsides, waste places, thickets, fields. From Europe. [LYCHNIS VISCARIA Linnaeus; VISCARIA VULGARIS Bernhardi]

SILENE VULGARIS (Moench) Garcke subsp. VULGARIS - Bladder Campion. 2n = (12), 24, (48).

Waste places, roadsides, field borders. From Europe. [S. CUCUBALUS Wibel; S. LATIFOLIA (Miller) Britten & Rendle -- invalid name]

Silene hybrid

SILENE X HAMPEANA Meusel & K. Werner - .

[S. DIOICA (Linnaeus) Clairville X S. LATIFOLIA Poiret]

SILPHIUM (Family: Asteraceae)

SILPHIUM PERFOLIATUM Linnaeus var. PERFOLIATUM - Cup-plant. 2n = 14, (16).

Moist thickets, low, open woods, moist roadsides, waste places. From farther west and south.

SILYBUM (Family: Asteraceae)

SILYBUM MARIANUM (Linnaeus) Gaertner - Milk Thistle. 2n = 34.

Waste places. From Eurasia, northern Africa.

SINAPIS (Family: Brassicaceae)

SINAPIS ALBA Linnaeus - White Mustard. 2n = 24.

Roadsides, waste places, railroads. From Eurasia. [BRASSICA ALBA (Linnaeus) Rabenhorst; B. HIRTA Moench]

SINAPIS ARVENSIS Linnaeus - Charlock. 2n = (16), 18.

Waste places, fields, roadsides. From Eurasia. [BRASSICA KABER (de Candolle) L.C. Wheeler; B. KABER var. PINNATIFIDA (Stokes) L.C. Wheeler; B. KABER var. SCHKUHRIANA (Reichenbach) L.C. Wheeler]

SISYMBRIUM (Family: Brassicaceae)

SISYMBRIUM ALTISSIMUM Linnaeus - Tumble-mustard. 2n = 14.

Waste places, fields, roadsides. From Eurasia, northwestern Africa.

SISYMBRIUM IRIO Linnaeus - London Rocket. 2n = 14, (16), (21), (28), (42), (56).

Roadsides, railroads, waste places. From Eurasia, northern Africa.

SISYMBRIUM LOESELII Linnaeus - False London Rocket. 2n = 14.

Waste places, fields, roadsides. From Eurasia.

SISYMBRIUM OFFICINALE (Linnaeus) Scopoli - Hedge-mustard. 2n = 14.

Waste places, roadsides, fields. From Eurasia, northern Africa. [S. OFFICINALE var. LEIOCARPUM de Candolle]

SISYMBRIUM ORIENTALE Linnaeus - Indian Hedge-mustard. 2n = 14.

Waste places, roadsides. From Eurasia, northern Africa.

SISYRINCHIUM (Family: Iridaceae)

Sisyrinchium albidum Rafinesque - . 2n = 32, (64).

Dry, sandy, open soil and thin woodlands.

Sisyrinchium angustifolium Miller - Stout Blue-eyed Grass. 2n = 96.

Meadows, fields, low woods, thickets, damp shores. [S. bermudiana misapplied; S. graminoides E.P. Bicknell]

Sisyrinchium atlanticum E.P. Bicknell - Eastern Blue-eyed Grass. 2n = 16, 32, 96.

Meadows, marshes, low woods.

Sisyrinchium fuscatum E.P. Bicknell - . 2n = 32.

Grasslands, mostly sandy soils. [S. arenicola E.P. Bicknell]

Sisyrinchium montanum Greene var. crebrum Fernald - Common Blue-eyed Grass. 2n = 32, 86, 96.

Fields, meadows, open woods. [S. angustifolium misapplied]

Sisyrinchium mucronatum Michaux - Slender Blue-eyed Grass. 2n = (30), 32.

Meadows, fields, sandy places, open woods.

SIUM (Family: Apiaceae)

Sium suave Walter - Water-parsnip. 2n = 12, (22).

Swamps, shores, meadows, wet thickets, brooks, shallow water of streams. [S. carsonii Durand ex A. Gray]

SMILAX (Family: Smilacaceae)

Smilax glauca Walter - Sawbrier. 2n = 28, 32.

Sandy thickets, open woods. [S. glauca Walter var. leurophylla S.F. Blake]

Smilax herbacea Linnaeus - Carrion-flower. 2n = 26.

Rich thickets, low woodlands.

Smilax rotundifolia Linnaeus - Common Greenbrier. 2n = ?

Woodlands, thickets.

Smilax tamnoides Linnaeus - China-root. 2n = ?

Low woodlands, thickets. [S. tamnoides var. hispida (Muhlenberg ex Torrey) Fernald; S. hispida Muhlenberg ex Torrey]

SOLANUM (Family: Solanaceae)

SOLANUM CAPSICOIDES Allioni - Cockroach-berry. 2n = 24.

Waste places. From South America. [S. SPHAEROCARPUM Moricand]

SOLANUM CAROLINENSE Linnaeus var. CAROLINENSE - Horse-nettle. 2n = 24, (48).

Dry fields, openings, roadsides, railroads, waste places, especially in sandy soil. From farther south.

SOLANUM CITRULLIFOLIUM A. Braun var. CITRULLIFOLIUM - . 2n = 24.

Waste places. From Texas, Mexico..

SOLANUM DULCAMARA Linnaeus - Climbing Nightshade. 2n = 24, (48), (72).

Moist thickets, clearings, streambanks, roadsides, waste places. From Eurasia, northern Africa. [S. DULCAMARA var. VILLOSISSIMUM Desvaux]

Solanum emulans Rafinesque - Eastern Black Nightshade. 2n = 24.

Woodlands, shores, thickets, waste places, usually moist soil. [S. americanum misapplied; S. nigrum misapplied; S. ptychanthum misapplied]

SOLANUM LYCOPERSICUM Linnaeus - Garden Tomato. 2n = 24, (36), (48).

Waste places, roadsides, railroads, shores, streambanks. From Mexico. [LYCOPERSICON ESCULENTUM Miller]

SOLANUM MELONGENA Linnaeus - Eggplant. 2n = 24, (36), (48).

Waste places. From Africa.

SOLANUM NIGRUM Linnaeus - European Black Nightshade. 2n = 24, (36), 48, 72, (96), (144).

Sea beaches, waste places. From Eurasia, northern Africa.

SOLANUM NITIDIBACCATUM Bitter - . 2n = 24.

Waste places, field and woodland margins, roadsides. From South America. [S. PHYSALIFOLIUM Rusby; S. SARACHOIDES misapplied]

SOLANUM PSEUDOCAPSICUM Linnaeus - Jerusalem-cherry. 2n = 24.

Waste places. From Mexico, Central America, Caribbean, South America.

SOLANUM ROSTRATUM Dunal - Buffalo-bur. 2n = 24.

Waste places, railroads, shores. From farther west. [S. CORNUTUM misapplied]

SOLANUM SARRACHOIDES Sendtner - Hairy Nightshade. 2n = 24.

Roadsides, waste places. From South America.

SOLANUM SISYMBRIIFOLIUM Lamarck - Sticky Nightshade. 2n = 24, (72).

Waste places. From South America.

SOLANUM TRIFLORUM Nuttall - . 2n = 24.

Waste places. From farther west.

SOLANUM TUBEROSUM Linnaeus - Potato. 2n = 24, (36), 48, (60), (72), (96).

Waste places, roadsides, railroads, fields. From western South America.

SOLANUM VILLOSUM Miller - . 2n = 48, (96).

Waste places. From southern Europe.

SOLIDAGO (Family: Asteraceae)

Solidago altissima Linnaeus subsp. altissima - 2n = (36), 54.

Clearings, fields, meadows, thickets, roadsides, waste places. [S. canadensis Linnaeus var. scabra (Muhlenberg ex Willdenow) Torrey & A. Gray]

Solidago arguta Aiton var. arguta - 2n = 18.

Open woods, clearings, roadsides.

Solidago bicolor Linnaeus - Silverrod. 2n = 18.

Dry, open, sterile soils, open woods, rocky slopes, roadsides.

Solidago brendae Semple - Brenda's Goldenrod. 2n = 18.

Roadsides.

Solidago caesia Linnaeus var. caesia - Blue-stem Goldenrod. 2n = 18.

Open or rich woods, woods margins, clearings, thickets.

Solidago canadensis Linnaeus var. canadensis - 2n = 18, (36).

Fields, roadsides, thickets, clearings, open woods.

Solidago canadensis Linnaeus var. hargeri Fernald - 2n = 18.

Fields, roadsides, thickets, clearings.

Solidago erecta Banks ex Pursh - Slender Goldenrod. 2n = 18.

Woods, sandy banks, roadsides.

Solidago flexicaulis Linnaeus - Zig-zag Goldenrod. 2n = 18, (27), 36, (90).

Rich woods, thickets.

Solidago gigantea Aiton - 2n = 18, 36, 54.

Damp thickets, meadows, stream banks, fields, swamps, open woods, roadsides. [S. gigantea var. leiophylla Fernald; S. gigantea var. serotina (Kuntze) Cronquist]

Solidago hispida Muhlenberg ex Willdenow - 2n = 18, (36).

Dry, open, rocky woods, usually in calcareous soil. [S. hispida var. lanata (Hooker) Fernald; S. bicolor Linnaeus var. concolor Torrey & A. Gray; S. bicolor var. lanata (Hooker) A. Gray]

Solidago juncea Aiton - Early Goldenrod. 2n = 18.

Fields, dry, open soil.

Solidago latissimifolia Miller - 2n = 18, 36, 54.

Swamps, meadows, low thickets. [S. elliottii Torrey & A. Gray var. elliottii; S. elliottii var. ascendans Fernald]

Solidago leiocarpa de Candolle - Cutler’s Alpine Goldenrod. 2n = 36.

Granitic alpine areas. [S. cutleri Fernald; S. multiradiata misapplied]

Solidago lepida de Candolle subsp. fallax (Fernald) Semple - 2n = 18.

Thickets, shores. [S. lepida var. molina Fernald]

Solidago macrophylla Banks ex Pursh - 2n = 18.

Shaded, rocky, mountain slopes. [S. macrophylla var. thyrsoidea (E. Meyer) Fernald]

Solidago nemoralis Aiton subsp. nemoralis - Gray Goldenrod. 2n = 18, 36.

Dry fields, open, sandy or gravelly soils, roadsides.

Solidago odora Aiton subsp. odora - Sweet Goldenrod. 2n = 18.

Dry, open woods, clearings, roadsides.

Solidago patula Muhlenberg ex Willdenow subsp. patula - Rough-leaved Goldenrod. 2n = 18.

Calcareous swamps, meadows, swales, wet woods and moist roadsides.

Solidago ptarmicoides (Torrey & Gray) B. Boivin - Snowy Aster. 2n = 18.

Dry, usually calcareous, ledges. [Aster ptarmicoides Torrey & Gray; Oligoneuron album (Nuttall) G.L. Nesom]

Solidago puberula Nuttall subsp. puberula - 2n = 18.

Dry, open woods, clearings, sandy or rocky shores of ponds and streams, roadsides.

Solidago rigida Linnaeus subsp. rigida - 2n = (18), 36.

Dry, open woods, clearings, thickets, near salt marshes, roadsides. [Oligoneuron rigidum (Linnaeus) Small]

Solidago rugosa Miller var. rugosa - 2n = 18, (36).

Moist, open soil, fields, thickets, borders of woods and streams. [S. rugosa var. villosa (Pursh) Fernald]

Solidago rugosa Miller var. sphagnophila C. Graves - 2n = 18, 54.

Swamps, meadows, wet thickets. [S. aestivalis E.P. Bicknell]

Solidago rugosa Miller subsp. aspera (Aiton) Cronquist - 2n = 18, 36.

Open woods, fields, thickets, roadsides. [S. aspera Aiton]

Solidago sempervirens Linnaeus subsp. sempervirens - Seaside Goldenrod. 2n = 18.

Salt marshes, seashores, tidal rivers, heavily-salted roadsides.

Solidago sempervirens Linnaeus subsp. mexicana (Linnaeus) Semple - Seaside Goldenrod. 2n = 18.

Salt marshes, seashores, tidal rivers, heavily-salted roadsides.

Solidago simplex Kunth var. monticola (Porter) G.S. Ringius - 2n = 36.

Dry, serpentine soils, rocky, granite barrens below alpine slopes. [S. glutinosa Nuttall var. randii (Porter) Cronquist (in part); S. randii (Porter) Britton (in part)]

Solidago simplex Kunth var. racemosa (Greene) G.S. Ringius - Riverbank Goldenrod. 2n = 36, 54.

Dry, usually calcareous rocks and ledges along rivers. [S. glutinosa Nuttall var. racemosa (Greene) Cronquist; S. racemosa Greene; S. randii (Porter) Britton (in part)]

Solidago speciosa Nuttall var. speciosa - 2n = 18, 36.

Fields, open woods, thickets, roadsides.

Solidago squarrosa Muhlenberg - Stout Goldenrod. 2n = 18.

Dry or rocky, open woods, rocky openings, thickets, fields, roadsides.

Solidago uliginosa Nuttall - Bog Goldenrod. 2n = 18, 36.

Bogs, swamps, meadows, marshes, fens, shores, usually sphagnous habitats. [S. uliginosa var. linoides (Torrey & A. Gray) Fernald; S. uliginosa var. terra-novae (Torrey & A. Gray) Fernald; S. purshii Porter]

Solidago ulmifolia Muhlenberg ex Willdenow var. ulmifolia - 2n = 18.

Dry, open or rocky woods, thickets, occasionally meadows.

Solidago hybrids

Solidago altissima Linnaeus X S. rugosa Miller var. rugosa - .

Solidago altissima Linnaeus X S. sempervirens Linnaeus var. sempervirens - .

Solidago arguta Aiton X S. bicolor Linnaeus - .

Solidago arguta Aiton X S. juncea Aiton - .

Solidago arguta Aiton X S. nemoralis Aiton - .

Solidago arguta Aiton X S. patula Muhlenberg ex Willdenow - .

Solidago X asperula Desfontaines (pro species) - .

[S. rugosa Miller var. rugosa X S. sempervirens Linnaeus subsp. sempervirens]

Solidago bicolor Linnaeus X S. caesia Linnaeus - .

Solidago bicolor Linnaeus X S. hispida Muhlenberg ex Willdenow - .

Solidago bicolor Linnaeus X S. nemoralis Aiton - .

Solidago bicolor Linnaeus X S. odora Aiton - .

Solidago bicolor Linnaeus X S. puberula Nuttall - .

Solidago bicolor Linnaeus X S. rugosa Miller var. rugosa - .

Solidago caesia Linnaeus X S. flexicaulis Linnaeus - .

Solidago caesia Linnaeus X S. juncea Aiton - .

Solidago caesia Linnaeus X S. rugosa Miller var. rugosa - .

Solidago X calcicola (Fernald) Fernald (pro species) - .

[S. macrophylla Banks ex Pursh X S. ?]

Solidago canadensis Linnaeus var. canadensis X S. gigantea Aiton - .

Solidago canadensis Linnaeus var. canadensis X S. juncea Aiton - .

Solidago canadensis Linnaeus var. canadensis X S. rugosa Miller var. rugosa - .

Solidago canadensis Linnaeus var. hargeri Fernald X S. rugosa Miller var. rugosa - .

Solidago gigantea Aiton X S. rugosa Miller var. rugosa - .

Solidago gigantea Aiton X S. sempervirens Linnaeus subsp. sempervirens - .

Solidago juncea Aiton X S. nemoralis Aiton - .

Solidago juncea Aiton X S. sempervirens Linnaeus subsp. sempervirens - .

Solidago latissimifolia Miller X S. rugosa Miller var. sphagnophila C. Graves - .

Solidago leiocarpa de Candolle X S. simplex Kunth var. monticola (Porter) G.S. Ringius - .

Solidago macrophylla Banks ex Pursh X S. rugosa Miller var. rugosa - .

Solidago nemoralis Aiton X S. sempervirens Linnaeus subsp. sempervirens - .

Solidago nemoralis Aiton X S. speciosa Nuttall - .

Solidago odora Aiton X S. rugosa Miller var. rugosa - .

Solidago rugosa Miller var. rugosa X S. ulmifolia Muhlenberg ex Willdenow - .

SONCHUS (Family: Asteraceae)

SONCHUS ARVENSIS Linnaeus subsp. ARVENSIS - Corn Sow-thistle. 2n = 18, 36, (40), (45), 54, (60), (64).

Waste places, fields, roadsides, shores, usually wet sites. From Eurasia, northern Africa.

SONCHUS ARVENSIS Linnaeus subsp. ULIGINOSUS (M. Bieberstein) Nyman - 2n = (27), 36.

Waste places, fields, roadsides, shores, usually wet sites. From Eurasia. [S. ARVENSIS var. GLABRESCENS Günther, Grabowski, & Wimmer; S. ULIGINOSUS M. Bieberstein]

SONCHUS ASPER (Linnaeus) Hill - Prickly Sow-thistle. 2n = 18, (36).

Waste places, roadsides, sea shores. From Eurasia, northern Africa.

SONCHUS OLERACEUS Linnaeus - Common Sow-thistle. 2n = (18), 32, (36), (64).

Waste places, fields, roadsides, sea shores. From Eurasia, northern Africa.

SORBARIA (Family: Rosaceae)

SORBARIA SORBIFOLIA (Linnaeus) A. Braun - False Spiraea. 2n = 18, 36.

Roadsides, waste places. From eastern Asia.

X SORBARONIA (Family: Rosaceae)

X SORBARONIA FALLAX (C.K. Schneider) C.K. Schneider - .

[Aronia melanocarpa (Michaux) Elliott X SORBUS AUCUPARIA Linnaeus; PYRUS X FALLAX (C.K. Schneider) Fernald]

X SORBARONIA HYBRIDA (Moench) C.K. Schneider - .

[Aronia arbutifolia (Linnaeus) Persoon X SORBUS AUCUPARIA Linnaeus; ARONIA HYBRIDA (Moench) Zabel; PYRUS HYBRIDA Moench; SORBUS X HYBRIDA (Moench) C.K. Schneider not Linnaeus – illegitimate name]

X Sorbaronia jackii Rehder - .

[Aronia X prunifolia (Marshall) Rehder X Sorbus americana Marshall; Pyrus X jackii (Rehder) Fernald]

X Sorbaronia monstrosa (Zabel) C.K. Schneider - .

[Aronia X arbutifolia (Linnaeus) Persoon X Sorbus americana Marshall]

X Sorbaronia sorbifolia (Poiret) C.K. Schneider - .

[Aronia melanocarpa (Michaux) Elliott X Sorbus americana Marshall; Aronia sargentii (Dippel) Zabel; Pyrus X mixta Fernald; Sorbus X sargentii Dippel; S. X sorbifolia (Poiret) Hedlund]

SORBUS (Family: Rosaceae)

Sorbus americana Marshall - American Mountain-ash. 2n = 34.

Cool, moist woods, mountain slopes. [Pyrus americana (Marshall) Sprengel]

SORBUS AUCUPARIA Linnaeus - European Mountain-ash. 2n = (30), 34, (51).

Woods, fields, roadsides, woodland borders, thickets. From Eurasia. [PYRUS AUCUPARIA (Linnaeus) Gaertner]

Sorbus decora (Sargent) C.K. Schneider - Northern Mountain-ash. 2n = 34, 68.

Wet woods, high mountain slopes, freshwater shores. [S. decora var. groenlandica (C.K. Schneider) G.N. Jones; Pyrus decora (Sargent) Hyland; P. decora var. groenlandica (C.K. Schneider) Fernald]

SORBUS INTERMEDIA (Ehrhart) Persoon - Swedish Whitebeam. 2n = 68.

Roadsides. From Europe. [PYRUS INTERMEDIA Ehrhart]

SORGHASTRUM (Family: Poaceae)

Sorghastrum nutans (Linnaeus) Nash - Indian Grass. 2n = (20), 40, (80).

Dry fields, roadsides, rocky shores of rivers.

SORGHUM (Family: Poaceae)

SORGHUM BICOLOR (Linnaeus) Moench - Sorghum. 2n = (10), 20, (40).

Waste places. From Africa. [S. VULGARE Persoon]

SORGHUM HALEPENSE (Linnaeus) Persoon - Johnson Grass. 2n = (18), (20), 40, (60).

Waste places. From the Mediterranean.

SPARGANIUM (Family: Typhaceae)

Sparganium americanum Nuttall - . 2n = ?

Muddy shores, shallow water.

Sparganium androcladum (Engelmann) Morong - . 2n = ?

Muddy shores, marshes, shallow water.

Sparganium angustifolium Michaux - . 2n = 30.

Shallow or deep water, shores. [S. multipedunculatum (Morong) Rydberg]

Sparganium emersum Rehmann - . 2n = 30.

Muddy shores, marshes, shallow water [S. chlorocarpum Rydberg; S. chlorocarpum var. acaule (Beeby) Fernald]

Sparganium eurycarpum Engelmann - . 2n = 30.

Mostly basic, muddy shores, marshes, shallow water.

Sparganium fluctuans (Morong) B.L. Robinson - . 2n = ?

Non-basic lakes and ponds.

Sparganium natans Linnaeus - . 2n = 30.

Shallow pools, streams, shores, bogs. [S. minimum Fries ex Wallroth]

Sparganium hybrids

Sparganium americanum Nuttall X S. fluctuans (Morong) B.L. Robinson - .

Sparganium angustifolium Michaux X S. emersum Rehmann - .

SPARTINA (Family: Poaceae)

Spartina alterniflora Loiseleur - Smooth Cordgrass. 2n = (40), (56), (60), 62.

Salt marshes, tidal shores. [S. alterniflora var. pilosa (Merrill) Fernald]

Spartina cynosuroides (Linnaeus) Roth - Big Cordgrass. 2n = 40, 42.

Salt marshes. [S. cynosuroides var. polystachya (Michaux) Beal]

Spartina patens (Aiton) Muhlenberg - Saltmeadow Cordgrass. 2n = (28), 40.

Salt marshes. [S. patens var. monogyna (M.A. Curtis) Fernald]

Spartina pectinata Link - Prairie Cordgrass. 2n = (28), 40, (80).

Shores, meadows, lowlands. [S. pectinata var. suttiei (Farwell) Fernald]

SPARTINA hybrid

Spartina X caespitosa A.A. Eaton (pro species) - .

Salt marsh borders, beaches. [S. patens (Aiton) Muhlenberg X S. pectinata Link; S. patens var. caespitosa (A.A. Eaton) Hitchcock]

SPERGULA (Family: Caryophyllaceae)

SPERGULA ARVENSIS Linnaeus - Corn Spurrey. 2n = 18, (36).

Roadsides, fallow fields. From Eurasia. [S. ARVENSIS var. SATIVA (Boenninghausen) Mertens & W.D.J. Koch]

SPERGULA MORISONII Boreau - Pearlwort Spurrey. 2n = 18.

Sandy roadsides, disturbed ground. From Europe.

SPERGULA PENTANDRA Linnaeus - Wingstem Spurrey. 2n = 18.

Sandy fields, disturbed ground. From Eurasia, northern Africa.

SPERGULARIA (Family: Caryophyllaceae)

Spergularia canadensis (Persoon) G. Don var. canadensis - Northern Sand-spurrey. 2n = 36.

Salt marshes, tidal shores.

SPERGULARIA RUBRA (Linnaeus) J. Presl & C. Presl - Red Sand-spurrey. 2n = (18), (27), 36.