The Mobius Arch in the Alabama Hills -- This rock arch perfectly frames Mount Whitney in the center opening.
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Noxious Weeds


Poison-hemlock (Conium maculatum L.)

Carrot family (Apiaceae) 

Photo collage of Poison-hemlock 

GROWTH HABIT:Poison-hemlock was intentionally introduced into North America as a garden ornamental in the early 1800's.  The plant ususally develops as a biennial but may occasionally act as a winter annual or short-lived perennial.  It is erect, extensively branched and grows to a height of 6 to 10.5 feet (1.8 to 3.2 m).  The stems are hollow and distinctively ridged and marked by purplish-red splotches.
LEAVES: The leaves are dark green and somewhat triangular and fern-like.
FLOWERS:The flowers are borne in numerous, 1.6 to 2.4 inches (4 to 6 cm) wide, umbrella-shaped clusters from May to August.
SEEDS:The seeds are oval, flattened and light brown in color.  They are 0.16 inches (4 mm) long and have prominent longitudinal, wavy ribs.
OTHER:The white taproot is long, fleshy and usually unbranched.
KEY CHARACTERS:
  • The stems are hollow and distinctively ridged and marked by purplish-red splotches.
DISTRIBUTION:Throughout pastures and waterways within Inyo/Mono Counties