Heracleum maximum

Species category

Weed

Common name

common cowparsnip

Diagnostic characters

Planting unit

MericarpMericarp:
One-half of a two-sectioned fruit known as a schizocarp (e.g. carrot).

Shape

OvalOval:
Broadly elliptic.
with a curve on the ventralVentral:
Adaxial; of the side of an organ facing the axis (compare dorsal).
side and flat on the dorsalDorsal:
Upper side or back of a seed or fruit.
side

Size

  • Length 5–6 mm
  • Width 4.5–5 mm
  • Thickness 1.5–2 mm

Color

White with brown longitudinal lines

Texture

Smooth have longitudinal ribs

Other structures

Scar on the apicalApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.
end and the margin is winged.

Identification notes

Longitudinal brown lines between ribs. (Four on the ventralVentral:
Adaxial; of the side of an organ facing the axis (compare dorsal).
side and two on the dorsalDorsal:
Upper side or back of a seed or fruit.
side).

Noxious weed seed categories

Not listed

AOSA examination list

Not included

Nomenclature

Family

Apiaceae

Valid name

Heracleum maximum W. Bartram

Synonyms

Heracleum lanatum Michx.
Heracleum sphondylium L. var. lanatum (Michx.) Dorn
Heracleum sphondylium L. ssp. montanum (Schleich. ex Gaudin) Briq.

 Heracleum maximum.  Mericarps with longitudinal brown lines between the ribs, there are four on the ventral side and two on the dorsal side. Photo by Julia Scher, USDA-APHIS-PPQ.
Heracleum maximum. Mericarps with longitudinal brown lines between the ribs, there are four on the ventral side and two on the dorsal side. Photo by Julia Scher, USDA-APHIS-PPQ.