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News and updates from the statewide UC Master Gardener Program office.
on June 20, 2013 at 2:32 PM
A friend of mine suffered poisoning with very unusual symptoms. She is legally blind and didn't know what she had encountered until she brought a sample of the plant to a local nursery. I did not realize it was so common in residential areas.
by Christine Holding
on November 6, 2016 at 11:02 AM
We think this is what killed our cat. We wish we would have seen your article sooner. :(
by Susie
on March 22, 2017 at 1:48 PM
This looks like a weed I have been fighting in my yard, and have seen on local hiking trails, and have been trying to identify. We call the seeds of this plant Hedgehogs because they are tiny oval burrs that tenaciously stick to absolutely everything; clothes, shoes, animals. Does this sound like the Poison Hemlock you describe here? Thank you.
by Kurt Wx
on March 25, 2017 at 1:52 PM
Poison hemlock looks very similar to Queen Anne's Lace, and they both grow in similar conditions (low altitudes, meadows, coastal trails, etc). Poison hemlock has purple blotches along its hairless hollow stems and rounded flower umbels when blooming. QEA has hairy stems, flatter flower spreads and no color markings on its stem.
by Ellen S
on June 5, 2017 at 6:46 PM
Hi there! Thank you for all the information on your website. I have been doing a search for poison hemlock and found your photo at I'm wondering why this photo doesn't show 2 of the characteristics that are commonly reported for poison hemlock: 1) the purple blotchy main stem, and 2) the rosette leaf structure at the base (which you have reported on your website to appear in the first year).  
Could you please tell me what stage (how old) you think the poison hemlock is in your picture at the above link? It looks exactly like what I have in my yard. In my yard however, the stalk is so thin (about an 8th of an inch) and the sparse, leggy plant reaches 6 ft tall at the highest. At most, the stem that attaches to the tap root is less than an 8th of an inch and there is no rosette or fern-like leaves at the base. The leave are just like those pictured in your picture (sparse up the stems).  
The seed pods are barbed and the stick to my clothes-- they are very hard to get off. Is this characteristic of poison hemlock seed pods??  
Thanks for any information... I have two kids that eat the nystirtium nearby where I have found the suspect poison hemlock.
Reply by Melissa G. Womack
on June 7, 2017 at 10:53 AM
Hi Ellen,  
Hemlock is a biennial (takes two years to develop and reproduce). In year one it is usually low to the ground and just a clump of leaves. In year 2 it bolts and flowers. This plant is in its second year,  
We are happy to help identify what you have in your landscape if you take several images of the plant and a close-up of the leaves. Email me directly at  
by Todd
on June 10, 2017 at 9:58 AM
I have seen the same weed as Susie that looks VERY close to Poison Hemlock (the leaves look like Poison Hemlock), but has burr-like seeds and I suspect is an Annual...
by Carol Constantine
on June 13, 2017 at 2:44 PM
In addition to the purple blotches on the stem, hemlock has an unpleasant musty odor commonly described as "mousy".
by Deborah Beale
on June 30, 2019 at 10:56 AM
Hemlock seeded into an herbes pot on my deck & I tasted a piece of a leaf, thinking it was cilantro. That was a bad mistake. I recovered with no liver damage, but getting through the poisoning lasted 3 weeks and the recovery another 3 weeks. I am very pro eradication of hemlock, as much as possible - lol. - from Santa Cruz county
by Siti Nur Amalia
on July 13, 2019 at 6:58 AM
what's the effect if human contact with this plant?
by Bouncedancer
on November 5, 2019 at 10:30 AM
Siti Nur Amalia, I know people who got a neurological episode -- fainting and after-effects that could last weeks -- just from their skin coming in contact with the broken stem.
by Kaytee vossen
on May 28, 2020 at 8:41 PM
Gosh. Thankyou so much. I believe I’ve seen this plant so will look more closely and stop tasting plants!
by Kathleencole
on May 2, 2022 at 8:07 PM
I just finished reading an article in April, 2022 Good Housekeeping magazine about a man who almost died from cutting poison hemlock in his yard.S
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