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Giant Hogweed Heracleum mantegazzianum

Other plants called Giant Hogweed:

This plant has high severity poison characteristics.
See below
This plant is an invasive species in North Carolina
Description

Giant hogweed is an herbaceous perennial flowering plant in the Apiaceae (carrot) family.  It is a very large plant reaching heights of 20 feet tall.  It is a noxious weed in several states and is a class A noxious weed in North Carolina and so far found only in Watauga County. The plant can take several years to flower but once it flowers and sets seeds it dies. However, thousands of seeds are formed.

Read more at https://lee.ces.ncsu.edu/2018/07/hard-facts-about-hogweed/.  The rapid rate at which is grows means it can outcompete native plants, especially along riparian corridors.  

Insects, Diseases, and Other Plant Problems:  The sap of the plant is highly toxic and can cause sensitivity to UV rays causing severe blistering and burning from sun exposure.  Removing this weed manually can therefore be quite dangerous and requires proper skin protection.  

See this plant in the following landscape:
Cultivars / Varieties:
Tags:
#invasive#weedy#perennial weed
 
Cultivars / Varieties:
Tags:
#invasive#weedy#perennial weed
  • Attributes:
    Genus:
    Heracleum
    Species:
    mantegazzianum
    Family:
    Apiaceae
    Life Cycle:
    Perennial
    Country Or Region Of Origin:
    Transcaucasus
  • Whole Plant Traits:
    Plant Type:
    Herbaceous Perennial
    Perennial
    Weed
    Growth Rate:
    Rapid
    Maintenance:
    High
  • Cultural Conditions:
    USDA Plant Hardiness Zone:
    3a, 3b, 4a, 4b, 5b, 5a, 6a, 6b, 7a, 7b, 8a, 8b, 9b, 9a
  • Fruit:
    Display/Harvest Time:
    Fall
    Fruit Type:
    Schizocarp
    Fruit Length:
    < 1 inch
    Fruit Width:
    < 1 inch
    Fruit Description:
    Ellpicial and dry, resemlbe small apples .3" to .4" long and 1/4" wide. They have resin canals inside that are brown. Seeds are cream colored, flat with brown teardrop markings. Produced in August.
  • Flowers:
    Flower Color:
    White
    Flower Inflorescence:
    Umbel
    Flower Bloom Time:
    Summer
    Flower Description:
    Large white compound umble (carrot-like) inflorecences appear from June-July. They can reach 2.5' across.
  • Leaves:
    Leaf Color:
    Green
    Leaf Type:
    Simple
    Leaf Margin:
    Lobed
    Hairs Present:
    No
    Leaf Description:
    Very large, up to 3-5 feet wide green deeply lobed leaves
  • Stem:
    Stem Color:
    Green
    Stem Is Aromatic:
    No
    Stem Cross Section:
    Angular
    Stem Form:
    Straight
    Stem Surface:
    Hairy (pubescent)
    Stem Description:
    Hollow green stems with dark reddish-purple splotches and prominent coarse white hairs angled stems 1-3 inches in diameter.
  • Landscape:
    Problems:
    Contact Dermatitis
    Invasive Species
    Poisonous to Humans
    Weedy
  • Poisonous to Humans:
    Poison Severity:
    High
    Poison Symptoms:
    Sap from the plant causes senstiviety to UV rays which results in severe burns and blistering of the skin.
    Poison Toxic Principle:
    Furanocoumarins
    Causes Contact Dermatitis:
    Yes
    Poison Part:
    Sap/Juice