Weed Information: Solanum nigrum (nightshade, black)
Back to Plant List

Solanum nigrum (nightshade, black)

Family: Solanaceae

Description

Black nightshade is a common annual weed of cultivated cropland. As with many of the nightshades, the fruit is a berry, green when immature but black when ripe. This species is very similar to hairy nightshade, the major difference being that as the fruit matures in hairy nightshade (Solanum sarrachoides), the sepals become enlarged and cover the lower half of the fruit whereas in black nightshade they enlarge only slightly. Some sources lump this species with eastern black nightshade (Solanum ptycanthum).

Characteristics

Flower Color
  • White
Inflorescence Type (How the flowers are arranged on the plant)
  • Internodal cluster
Number of Petals
  • 5 petals
Petal Separation
  • United at base only (<25% length)
  • United from 25% - 75% length
Petal Tip
  • Pointed
Flower Symmetry
  • Flowers regular
Flower Length (Head length in the Asteraceae)
  • 4 mm (.16 inch)
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
  • 1.0 cm (.40 inch)
Flower Width (Head width in the Asteraceae)
  • 4 mm (.16 inch)
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
  • 1.0 cm (.40 inch)
Number of Sepals
  • 5 sepals
Sepal Separation
  • United at base < 25% length
  • United from 25% - 75% length
Sepal Tip
  • Pointed
  • Rounded
Flower Sex
  • Bisexual (perfect)
Number of Styles
  • 1 style
Number of Stamens
  • 5 stamens
Stamens Attached to the Petals
  • Stamens attached to the petals
Stamens Connate (united)
  • Filaments or anthers NOT united
  • Anthers united, syngynoecious

Carpel Separation
  • Carpels united (or one)
Number of Carpels
  • 2 carpels
Ovary Position
  • Superior (hypogynous)
Fruit Type
  • Berry, black
  • Berry, green
Fruit Length at Maturity
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
  • 1.0 cm (.40 inch)
  • 1.5 cm (.60 inch)
Fruit Width at Maturity
  • 5 mm (.20 inch)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
  • 1.0 cm (.40 inch)
  • 1.5 cm (.60 inch)
Burs
  • Fruit or seed NOT bur-like

Leaf Arrangement
  • Alternate
Leaf Type
  • Simple (including lobed leaves)
Stipules
  • Lacking
Tendrils
  • Tendrils absent
Venation
  • Pinnate
Petiole (leaf stem) Blade Ratio
  • Petiole < 25% total length
  • Petiole 25% - 75% total length
Leaf Length (blade PLUS petiole)
  • 2 - 4 cm (.80 - 1.60 inches)
  • 4 - 10 cm (1.60 - 4.0 inches)
Leaf Width
  • 1 - 2 cm (.40 - .80 inch)
  • 2 - 4 cm (.80 - 1.6 inches)
  • 4 - 10 cm (1.6 - 4.0 inches)
Leaf Shape (simple leaves only)
  • Deltoid (triangular)
  • Ovate
Leaf or Leaflet Margin
  • Crenate
  • Entire
  • Lobed
  • Undulate (sinuate, repand)
Leaf or Leaflet Blade Base
  • Acute (cuneate)
  • Acuminate (attenuate)
  • Truncate
Leaf or Leaflet Tip
  • Acute
  • Rounded (obtuse)
Leaf or Leaflet Blade Surface
  • Glabrous (NO hairs)
  • Pubescent
  • Strigose
Succulence
  • Not succulent

Milky Juice
  • Juice NOT milky (watery)
Woodiness
  • Herbaceous
Spines or Thorns
  • Spines or Thorns ABSENT
Aromatic (vegetative structures)
  • Not aromatic
  • Aromatic
Life Cycle
  • Annual
Growth Habit (while flowering)
  • Spreading ascending
  • Erect, spherical (bushy)
Plant Height at Maturity
  • 1 - 2 dm (4.0 - 8.0 inches)
  • 2 - 4 dm (8.0 - 16.0 inches)
  • 4 - 6 dm (1.3 - 2.0 feet)
Wind Dissemination
  • Not wind disseminated
Moisture Regime
  • Mesic
Chlorophyll
  • Present

Stem Cross Section
  • Round
Flowering Stem Leaves
  • Stem uniformly leafy
Main Stem Branches
  • Main stem branched

Root or Vegetative Propagule
  • Tap Root

US State
  • Alabama
  • Florida
  • Massachusetts
  • Maine
  • New Hampshire
  • New York
  • South Carolina
  • Virginia
  • Hawaii
  • Maryland
  • Alaska
  • California
  • Oregon
  • Washington
Other
  • Virgin Islands
  • District of Columbia
Canadian Province or Territory
  • Nova Scotia
  • Ontario
  • Newfoundland

  • The Biology of Canadian Weeds: Canadian Journal of Plant Science Vol:65Pg.401
  • California Growers Weed Identification Handbook, 1968 - 1998 University of California Publication # 4030-1, See page: 142
  • Common Weeds of the Canadian Prairies, 1963 (Cat# A53-1136-1) See page: 61
  • Common Weeds of the United States, 1971 (ISBN 0-486-20504-5) See page: 324
  • Common Weed Seedlings of the United States and Canada, 1978 Coop Ext. Univ. of Georgia, Athens, See page: 28
  • Gilkey`s Weeds of the Pacific Northwest, 1980 (ISBN 0-88246-039-0) See page: 253
  • How to Know the Weeds, 1972, (ISBN# 0-697-04880-2) See page: 135
  • Identification Guide to the Weeds of Quebec, 1999 (ISBN# 2-89457-174-7) See page: 147
  • Identifying Seedling and Mature Weeds (Southeastern US) 1980 North Carolina Agricultural Research Service, Bulletin #461 See page: 110
  • Manual of Ohio Weeds, 1931 Ohio Ag. Exp. Station Bull. # 475, See page: 75
  • Nebraska Weeds, 1979 Nebraska Dept. of Ag., Lincoln NE, See page: 168
  • Ontario Weeds, 1992 Agdex 640, Publication #505 See page: 184
  • Representative Missouri Weeds and Their Control, 1941 Univ. of Missouri Ag. Exp Station Bulletin #433, See page: 159
  • Selected Weeds of Oregon, 1985 and 1989 Supplement (s) Oregon State Dept. of Agriculture, See page: 59
  • Some Important Michigan Weeds, 1951 Mich. Ag. Exp. Station Bulletin #304, See page: 173
  • South Dakota Weeds, 1967 South Dakota State University, See page: 146
  • South Dakota Weeds 2002 South Dakota Dept. of Ag. 523 E. Capitol, Foss Bldg. Pierre, South Dakota 57501 See page: 123
  • S.W.S.S. Weed ID Guide, 1993 Section Number and Five letter code: 5 SOLNI
  • Weeds, 1955 (1980) Walter Conrad Muenscher, ISBN# 0-8014-1266-8 See page: 388, 389
  • Weeds, A Golden Guide, 1972 ISBN#0-307-24353-2 See page: 104, 105
  • Weeds and Poisonous Plants of Wyoming and Utah 1987 (ISBN 0-941570-06-1) See page: 116
  • Weeds of California, 1970, State of California Publications and Documents. See page: 391
  • Weeds of California and other Western States, 2007 (ISBN 13: 978-1-879906-69-3) See Page: 1528
  • Weeds of Eastern Washington and Adjacent Areas, 1972 (LOC 72-83635) See page: 242
  • Weeds of Nebraska and the Great Plains, 1994 (ISBN 0939870-00-4) See page: 526
  • Weeds of the Northeast, 1956, Univ. of Delaware Field Manual #1 See species #: 202
  • Weeds of the Northeast, 1997 Cornell University ISBN# 0-8014-8334-4 See page: 318, 374
  • Weeds of the Northern United States and Canada, 1964 Montgomery See page: 145
  • Weeds of the Northern U.S, and Canada, 1999 Royer and Dickinson, (ISBN# 1-55105-221-0) See page: 300-01, 303
  • Weeds of the Southern United States, 1975, North Carolina Ag. Extension Circular #599 See page: 41
  • Weeds of the United States and Their Control, Lorenzi 1987, ISBN# 0-442-25884-4 See page: 262
  • Weeds of the West, 1992 (ISBN 0941570-13-4) See page: 574
  • Weeds of the West, 2000 (ISBN 0941570-13-4) See page: 568
  • Weeds of Utah, 1971 UAES Special Report 21, See page: 80
  • Wildly Successful Plants, A Handbook of North American Weeds, 1977 (ISBN# 0-02-528850-4) See page: 26, 189
  • Listed as a `Weed` by the Biota of North America Program, 2008 x
  • Listed in the WSSA Composite List of Weeds X
Back to Plant List