Weed Information: Hypericum punctatum (St. Johnswort, spotted)
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Hypericum punctatum (St. Johnswort, spotted)

Family: Clusiaceae

Description

Note the numerous black glandular dots on the backs of the leaves. The sepals are black dotted and lined with black, while the petals display many translucent amber glands. This erect perennial generally has few branches below the inflorescence.

Characteristics

Flower Color
  • Yellow-orange
  • Yellow
Inflorescence Type (How the flowers are arranged on the plant)
  • Corymb
  • Cyme (simple or branched)
Number of Petals
  • 5 petals
Petal Separation
  • Completely free to base
Petal Tip
  • Rounded
Flower Symmetry
  • Flowers regular
Flower Length (Head length in the Asteraceae)
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
  • 9 mm (.36 inch)
Flower Width (Head width in the Asteraceae)
  • 9 mm (.36 inch)
  • 1.0 cm (.40 inch)
  • 1.5 cm (.60 inch)
Number of Sepals
  • 5 sepals
Sepal Separation
  • Completely free to base
Sepal Tip
  • Pointed
Flower Sex
  • Bisexual (perfect)
Number of Styles
  • 3 styles
  • 4 styles
  • 5 styles
Number of Stamens
  • more than 10 stamens
Stamens Attached to the Petals
  • Stamens NOT attached to the petals
Stamens Connate (united)
  • Filaments or anthers NOT united

Carpel Separation
  • Carpels united (or one)
Number of Carpels
  • 3 carpels
  • 4 carpels
  • 5 carpels
Ovary Position
  • Superior (hypogynous)
Fruit Type
  • Capsule, 3-celled
  • Capsule, > 3-celled
Fruit Length at Maturity
  • 6 mm (.24 inch)
  • 7 mm (.28 inch)
  • 8 mm (.32 inch)
Fruit Width at Maturity
  • 3 mm (.12 inch)
  • 4 mm (.16 inch)
  • 5 mm (.20 inch)
Burs
  • Fruit or seed NOT bur-like

Leaf Arrangement
  • Opposite
Leaf Type
  • Simple (including lobed leaves)
Stipules
  • Lacking
Tendrils
  • Tendrils absent
Venation
  • Arcuate
  • Pinnate
Petiole (leaf stem) Blade Ratio
  • Petiole absent (leaf sessile)
  • Petiole < 25% total length
Leaf Length (blade PLUS petiole)
  • 1 - 2 cm (.40 - .80 inch)
  • 2 - 4 cm (.80 - 1.60 inches)
  • 4 - 10 cm (1.60 - 4.0 inches)
Leaf Width
  • 5 - 10 mm (.20 - .40 inch)
  • 1 - 2 cm (.40 - .80 inch)
Leaf Shape (simple leaves only)
  • Elliptic
  • Oblanceolate
  • Oblong
Leaf or Leaflet Margin
  • Entire
Leaf or Leaflet Blade Base
  • Acute (cuneate)
  • Rounded
Leaf or Leaflet Tip
  • Rounded (obtuse)
Leaf or Leaflet Blade Surface
  • Punctate
Succulence
  • Not succulent

Milky Juice
  • Juice NOT milky (watery)
Woodiness
  • Herbaceous
  • Semi-woody
Spines or Thorns
  • Spines or Thorns ABSENT
Aromatic (vegetative structures)
  • Not aromatic
Life Cycle
  • Perennial
Growth Habit (while flowering)
  • Erect, columnar (narrow)
Plant Height at Maturity
  • 6 - 8 dm (2.0 - 2.6 feet)
  • 8 - 10 dm (2.6 - 3.3 feet)
Wind Dissemination
  • Not wind disseminated
Moisture Regime
  • Seasonally saturated
  • Mesic
Chlorophyll
  • Present

Stem Cross Section
  • Round
Flowering Stem Leaves
  • Stem leaves greatly reduced
  • Stem uniformly leafy
Main Stem Branches
  • Main stem unbranched
  • Main stem branched

Root or Vegetative Propagule
  • Rhizomatous

US State
  • Alabama
  • Arkansas
  • Connecticut
  • Delaware
  • Florida
  • Georgia
  • Illinois
  • Kansas
  • Kentucky
  • Louisiana
  • Massachusetts
  • Maine
  • Michigan
  • Missouri
  • Mississippi
  • North Carolina
  • New Hampshire
  • New Jersey
  • New York
  • Ohio
  • Pennsylvania
  • South Carolina
  • Tennessee
  • Texas
  • Virginia
  • Wisconsin
  • West Virginia
  • Indiana
  • Maryland
  • Rhode Island
  • Vermont
  • Iowa
  • Minnesota
  • Oklahoma
  • Nebraska
Other
  • District of Columbia
Canadian Province or Territory
  • Nova Scotia
  • Ontario
  • Quebec
  • Newfoundland

  • Weeds, 1955 (1980) Walter Conrad Muenscher, ISBN# 0-8014-1266-8 See page: 316
  • Weeds of the Northeast, 1956, Univ. of Delaware Field Manual #1 See species #: 66
  • Listed as a `Weed` by the Biota of North America Program, 2008 x
  • Listed in the WSSA Composite List of Weeds X
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