Poison hemlock (Conium maculatum) growing near the Truckee River in Mayberry Park, June 2015. Photo: K.McCutcheon.

Poison hemlock (Conium maculatum) blooming near the Truckee River, Mayberry Park, June 2015.  Photo: K. McCutcheon.

Poison Hemlock
Conium maculatum
  • An introduced species.
  • Carrot Family (Apiaceae).
  • Fern-like leaves.
  • Lacy white flowers bloom May-July.
  • Grows to 8 feet tall.
  • Poisonous. Do not pick!

Record Observations
Species Description:

Considered a noxious (harmful) weed in Nevada (USDA, 2015), poison hemlock was introduced from Europe and is now common along the banks of the Truckee. The fern-like leaves, lacy white flowers, stems, roots, and seeds are all extremely poisonous. They say that this is the plant that the ancient Greeks used to put prisoners to death, including Socrates (Vizgirdas & Rey-Visgirdas, 2006). Poison hemlock blooms from May – July and grows to eight feet tall (Blackwell, 2006).

Additional Images:
Poison hemlock leaves , April 2011. Photo: K.McCutcheon.

Poison hemlock leaves , April 2011. Photo: K.McCutcheon.


Poison hemlock leaves and flowers, June 2011. Photo: K.McCutcheon.

Poison hemlock leaves and flowers, June 2011. Photo: K.McCutcheon.

Photos & Information needed!

Do you have information on this species, or original photographs taken locally?  If so, please contribute photos and observations here, or email information to kelseymccutcheon@gmail.com. Thanks!

 

References:

Blackwell, L. R. (2006). Great Basin Wildflowers. Guilford, CT: Falcon Press.

USDA. 2015. Plants profile for Conium maculatum, Poison Hemlock. USDA Plants Database. Accessed 6/6/2015.

Vizgirdas, R. S., & Rey-Visgirdas, E. M. (2006). Wild Plants of the Sierra Nevada. Reno: University of Nevada Press.

 

Characteristics

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  3. Has poison hemlock growing along Truckee River’s walking trailer on Idlewild Drive riverfront walk?

  4. Has poison hemlock been found growing along truckee river in reno nv. Idlewild river front trail.

  5. Pingback: Poison Hemlock Can Kill You in 3 Hours or Less | Truckee River Outbreak 2017 | BeeHabitat.com

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