Poison Hemlock, beware

Kms

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For any who aren’t aware (I wasn’t), poison hemlock (Conium maculatum) is not only common but increasingly widespread across Pennsylvania, particularly in low-lying areas along roadsides, field edges, and near creeks and streams. The recent rain might also trigger an explosion of growth.

Beware stems with purple splotches!

IMG_5217.jpeg
 
Thanks, Mason. A few of us were probably rolling around in that stuff last weekend.

Love the avatar photo too 😉
 
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Although the warning from the meteorologist says it causes severe rashes, my understanding is that’s not always the case. The greater risks are ingestion, inhalation (even from sniffing the flowers), and exposure to mucous membranes.

Unlike the poison ivy irritant, this stuff contains neurotoxins which require more careful cleaning and can have nastier consequences.
 
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Already got my first dose of ivy. I knew it was there from past experience but it was my only access to a rising trout.

I got the ivy, and the fish. I got to return the fish but not the ivy.

I won't mess with hogweed. Stuff is nasty.

Hemlock looks like giant Queen Anne's Lace. I've seen it but managed to stay clear.
 
I thought that was called poison hogweed. Really bad stuff,
No, hogweed is a common name for cow parsnip, another plant that is apparently becoming more common in Pa based on a range map. I have never seen it in Pa. It is also poisonous to the touch.

Minor amounts to substantial stands of poison hemlock are now common along a couple of Lehigh Valley streams where I’ve spotted it over the last three years. Also saw it getting started at a spot along Kettle Ck last summer. The plants that I saw last week and this week were already 18”-24” tall, but no flower was present yet. Heed the op description above since you don’t want to mistake poison hemlock for queen anne’s lace.
 
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No, hogweed is a common name for cow parsnip, another plant that is apparently becoming more common in Pa based on a range map. I have never seen it in Pa. It is also poisonous to the touch.

Minor amounts to substantial stands of poison hemlock are now common along a couple of Lehigh Valley streams where I’ve spotted it over the last three years. Also saw it getting started at a spot along Kettle Ck last summer. The plants that I saw last week and this week were already 18”-24” tall, but no flower was present yet. Heed the op description above since you don’t want to mistake poison hemlock for queen anne’s lace.
Giant hogweed (Heracleum mantegazzianum) is not the same plant as Cow Parsnip (Heracleum maximum)
 
Aarrgh! Like we don’t have enough to worry about - how did this stuff invade PA? Naturally or accidentally?
 
Aarrgh! Like we don’t have enough to worry about - how did this stuff invade PA? Naturally or accidentally?

Poison hemlock is found in nearly every state in the US, with the exception of Alaska, Florida, Hawaii, and Mississippi, according to the USDA. It is commonly found in moist environments like roadsides, ditches, and edges of fields.

Common Habitats: Poison hemlock thrives in moist, disturbed areas like roadsides, ditches, field edges, and waste areas.....below 5000 feet, excluding desert regions, and prefers disturbed areas with some moisture and shade. It can be found in various locations, including fence lines, irrigation ditches, and other moist, waste places.
 
I really don’t care who said it, it’s still incorrect.
Feel free to take it up with the US Dept of Agriculture as well. https://www.nrcs.usda.gov/plantmaterials/mipmcpg14199.pdf

Hogweed or not; it’s not a name that I would choose, will use, or was even in my vocabulary. However, it appears on the list of common names for Cow Parsnip, which is the only name that I ever used, so perhaps there is a region of the US where cow parsnip is referred to as hogweed. Unlike birds and at least North American fish, there are no official common names for plants.
 
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Feel free to take it up with the US Dept of Agriculture as well. https://www.nrcs.usda.gov/plantmaterials/mipmcpg14199.pdf

Hogweed or not; it’s not a name that I would choose, will use, or was even in my vocabulary. However, it appears on the list of common names for Cow Parsnip, which is the only name that I ever used, so perhaps there is a region of the US where cow parsnip is referred to as hogweed. Unlike birds and at least North American fish, there are no official common names for plants.
I see no mention of “giant hogweed” in this publication.
 
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