Cow-parsnip

Heracleum sphondylium

Species distinguishing characteristics: 

  • Large, 3 parted, maple-like leaves
  • Large, hollow stalk
  • Large flower clusters
  • Flat seeds with stripes halfway to base and no prickles

Family Characteristics: 

  • Small flowers in “umbels,” which are clusters that radiate from a single point at the end of a stalk
  • Flowers have 5 petals, 5 sepals, and 5 stamens
  • All plant parts contain aromatic, volatile oils
  • Two-celled fruits with halves joined face-to-face
  • Stems are hollow between leaf joints and often have vertical ribs
  • Many plants in this family are culinary spices (e.g., dill, cilantro/coriander, fennel, caraway)
  • This family includes some of North America’s most poisonous plants

Growth habitat: 

Very large perennial, 1-3 m tall, with a single stem.

Leaves and stems: 

Hollow, vertically ribbed stem up to 2 inches in diameter.  Foliage is woolly-hairy when young, becoming smoother with age, and has a strong, pungent odor when crushed.  Large, coarsely toothed, divided leaves.  Upper leaves are lobed palmately, like fingers projecting from a palm, and divided into 3 large (10-40 cm long and wide) segments, similar to a maple leaf.  The base of the leaf stalk is winged, inflated and clasping the stem.  

Flowers: 

Numerous small white or slightly pinkish flowers in a large flat-topped cluster called compound umbels.  Flower clusters up to 1 foot across.  Beneath each flower and flower cluster is 5-10 narrow, linear bracts.

Roots: 

Stout taproot or cluster of fleshy, fibrous roots.

Seeds: 

Flattened sunflower-shaped seeds, 7-12 mm long.  Seeds have narrow ribs and dark lines that extend halfway to the base.

 

Habitat preferences: 

Rich, moist soils of streambanks, meadows, avalanche slopes, open forests, and roadsides.  Found in low to subalpine elevations.

Interesting facts: 

Seeds have a numbing effect on teeth and gums.  Volatile oils in the plant can cause skin blisters to form when affected areas are exposed to light.  Cow-parsnip is an important food source for grizzly bears (Ursus arctos), black bears (Ursus americanus), and elk (Cervus elaphus).  Various tribal groups ate peeled young stalks and leaf stems.

Biological Classification: