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Giant Hogweed Heracleum maximum

Previously known as:

  • Heracleum douglasii
  • Heracleum lanatum
  • Heracleum sphondylium
Phonetic Spelling
her-ah-KLEE-um MAKS-ih-mum
This plant has low severity poison characteristics.
See below
Description

Cow Parsnip is an herbaceous biennial or short-lived perennial wildflower in the carrot family native to North America and temperate Asia.  It is the only member of the genus Heracleum that is native to North America. In NC it is found in the western mountains. It inhabits marsh edges, streamsides, and damp open meadows.

The first year basal leaves are formed but the second year a 4-8 foot tall flowering stem emerges with a 6-8 inch compound umbel of many small white flowers. Its flowers attract a large diversity of pollinators.

This plant prefers silty or sandy loams in full sun to partial shade but will tolerate other soils if enough moisture is provided. They need moist conditions but not constantly wet ones. This plant can be weedy and should be used in naturalized areas as woodland edges or meadows. Great for attracting pollinators.

Do not get the sap from this plant on your skin and then be exposed to the sun as blistering can occur so be sure to wear gloves.

See this plant in the following landscape:
Cultivars / Varieties:
Tags:
#bees#sun#partial shade#biennial#white flowers#weedy#large leaves#slopes#meadow#stream banks#moist soil#thickets#native wildflower#larval host plant#malodorus#food source herbage#butterfly friendly#problem for cats#butterflies#problem for dogs#skin irritation#problem for horses
 
Cultivars / Varieties:
Tags:
#bees#sun#partial shade#biennial#white flowers#weedy#large leaves#slopes#meadow#stream banks#moist soil#thickets#native wildflower#larval host plant#malodorus#food source herbage#butterfly friendly#problem for cats#butterflies#problem for dogs#skin irritation#problem for horses
  • Attributes:
    Genus:
    Heracleum
    Species:
    maximum
    Family:
    Apiaceae
    Uses (Ethnobotany):
    Native Americans used the hollow stems to make deer calls
    Life Cycle:
    Biennial
    Perennial
    Recommended Propagation Strategy:
    Seed
    Country Or Region Of Origin:
    North America, Asia
    Distribution:
    AK , AZ , CA , CO , CT , DE , GA , IA , ID , IL , IN , KS , KY , MA , MD , ME , MI , MN , MO , MT , NC , ND , NE , NH , NJ , NM , NV , NY , OH , OR , PA , RI , SD , TN , UT , VA , VT , WA , WI , WV , WY Canada: AB , BC , NB , NL , NS , ON , PE
    Wildlife Value:
    Larval host of Anise swallowtail butterfly. Flowers attract many different pollinators
    Play Value:
    Wildlife Food Source
    Wildlife Larval Host
    Edibility:
    Young stems can be peeled, cooked and eaten. Roots can be cooked and eaten like parsnip.
  • Whole Plant Traits:
    Plant Type:
    Herbaceous Perennial
    Native Plant
    Wildflower
    Habit/Form:
    Erect
    Growth Rate:
    Medium
    Maintenance:
    Medium
    Texture:
    Fine
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    Clay
    Loam (Silt)
    Sand
    Soil pH:
    Acid (<6.0)
    Soil Drainage:
    Good Drainage
    Moist
    Occasionally Wet
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    4b, 4a, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a
  • Fruit:
    Fruit Color:
    Brown/Copper
    Cream/Tan
    Green
    White
    Display/Harvest Time:
    Fall
    Fruit Type:
    Schizocarp
    Fruit Length:
    < 1 inch
    Fruit Description:
    1/4 inch oval, flattened schizocarps are green with white margins. Mature to tan or brown and margins flatten into wings. They contain 2 seeds.
  • Flowers:
    Flower Color:
    White
    Flower Inflorescence:
    Umbel
    Flower Value To Gardener:
    Showy
    Flower Bloom Time:
    Summer
    Flower Petals:
    4-5 petals/rays
    Flower Size:
    < 1 inch
    Flower Description:
    6-8 inches across flat compound umbrels of many small white flowers. Blooms June-July
  • Leaves:
    Leaf Color:
    Green
    Leaf Value To Gardener:
    Showy
    Leaf Type:
    Compound (Pinnately , Bipinnately, Palmately)
    Leaf Arrangement:
    Alternate
    Leaf Shape:
    Obovate
    Orbicular
    Leaf Margin:
    Serrate
    Hairs Present:
    No
    Leaf Length:
    > 6 inches
    Leaf Width:
    3-6 inches
    Leaf Description:
    The lower to middle stem leaves are compound with 3 leaflets. Leaflets are 4-12 inches long with 3-5 lobes and serrated margins. Upper surface is green to yellow-green and rough with the undersides being paler with hairs along the veins. The upper stem leaves are simple, 3-lobed, serrated margins and 4 inches long and wide.
  • Stem:
    Stem Color:
    Green
    Stem Is Aromatic:
    No
    Stem Cross Section:
    Round
    Stem Form:
    Straight
    Stem Surface:
    Hairy (pubescent)
    Stem Description:
    The stem is grooved, woolly, hollow, and stout. They have a strong pungent odor when crushed.
  • Landscape:
    Landscape Location:
    Meadow
    Naturalized Area
    Riparian
    Slope/Bank
    Woodland
    Landscape Theme:
    Butterfly Garden
    Native Garden
    Pollinator Garden
    Attracts:
    Bees
    Butterflies
    Problems:
    Problem for Cats
    Problem for Dogs
    Problem for Horses
  • Poisonous to Humans:
    Poison Severity:
    Low
    Poison Symptoms:
    Photosensitization (sunburn, dermatitis)
    Poison Toxic Principle:
    Furanocoumarins
    Causes Contact Dermatitis:
    Yes