General: Perennial. Stem 1-3 m tall, hairs woolly.
Leaves: Leaves with widely sheathing petioles 10-40 cm long, upper sheaths enlarged, bladeless, blade 20-50 cm wide, round to kidney-shaped, leaflets 3, 10-40 cm wide, ovate to round, lobed or toothed, usually hairy.
Flowers: Inflorescence usually 10-20 cm in diameter, woolly or long-hairy, peduncle 5-20 cm long, involucre bracts 5-10, deciduous, narrow, 5-20 mm long, involucel bractlets similar to involucre bracts, rays 15-30, 5-10 cm long. Petals obovate, white.
Fruits: Fruit 8-12 mm long, obovate to heart-shaped, narrowed toward base, flat, winged, glabrous or hairy.
Account Author:: Fred Ganders, 2010.
USDA Species Characteristics
Flower Colour: White
Blooming Period: Early Summer
Fruit/Seed characteristics: Colour: Brown Present over the Summer
The native cow parsnip can be confused with the alien invasive, giant cow parsnip. Care should be taken with the identification.
Similar Species
To the casual observer, many members of the parsley family (Apiaceae) look similar. Many have white umbels of flowers and dissected leaves. Close inspection, however, shows noticeable differences in leaf shape (amount of dissection), flower (umbel) size, and habitat preferences. When identifying species in this family, habitat should be the first separator (wet or dry sites). In southwestern BC, cow parsnip is most easily confused with smaller plants of giant hogweed (Heracleum mantegazzianum), but may be separated from that species by its generally smaller size, leaf shape (it sports 3 distinct leaflets), and fruit shape. It may also be mistaken for poison hemlock (Conium maculatum). However, poison hemlock is generally much smaller than giant hogweed, with fern-like leaves and smaller flower umbels. Cow parsnip may also be mistaken for other wet-loving members of the Apiaceae, so care should be taken in the identification
Ecology
Ecological Framework for Heracleum maximum
The table below shows the species-specific information calculated from original data (BEC database) provided by the BC Ministry of Forests and Range. (Updated August, 2013)
