Poison Hemlock (Conium maculatum) at Merced, CA

Photo of Poison Hemlock (Conium maculatum)

lacy white flowerhead with many tiny flowers, more unopened flowerheads behind, and finely-cut leaves

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This poison hemlock plant was growing near the Merced National Wildlife Refuge in Merced, CA, located in the San Joaquin Basin of the Central California Valley. This invasive and highly toxic plant often forms large monocultures in agricultural areas, where it benefits from human-induced disturbance.

This photo is featured on our blog post Choosing The Best Common Names For Plants: Challenges & Solutions, where it is highlighted as an example of how its common name is confusing as "hemlock" also refers to trees of the Tsuga genus.

Photographer & Copyright

© P Holroyd

Photo Source

CC BY 4.0