These are growing on the side of the road in Western Pa. The stems are slightly hairy and I didn't observe any red splotches on them. I didn't check to see if the stems were hollow.
Sure looks like it. Are the stems smooth (not hairy) with red/burgundy splotches on them? Flowers appear to be 5 petaled. That's it! Don't let it in your garden!
The stems are slightly hairy/rough - not smooth. No red splotches that I could see. The plants are only about 3-4 ft tall so they are probably not fully mature. Could that be why there are no red splotches? Here is a picture of the stem and another overall picture to help with identification.
It appears to be the Apiaceae or (Parsley family). Poison hemlock gets to be 10 ft tall, and has the purple spots at all stages of growth. so that doesn't feel right. Leaves on Western waterhemlock look more like elderberry leaves and less fern like, roots when split in half top to tip have horizontal chambers. Maybe it's Wild caroway. It looks right but the info on that says it only gets 1 to 3 ft tall (who knows) I'm using both "Noxious weeds of Wash. State" and "Weeds of the West for reference and neither one is helping pin it down. Google: Western waterhemlock, Poison hemlock and Wild caraway. Another idea is to call your local Noxious weed board and see if they have any ideas. Hopefully others with more knowledge will come on board.
I didn't get a close up of the flowers, but they appear to have 5 petals. I will look up the information posted so far and will get a closeup of the flower head. I need to take another look at the plant and take note of whether leaves are alternate or opposite, whether stem is hollow, etc.
Not Conium maculatum; agree with Tyrlych it llooks much more like Anthriscus sylvestris (not sure if that's naturalised in the USA though).
So far it could be one of the following three plants although Hemlockparsley is unlikely because the stems are not smooth: Hemlockparsley (Conioselinum chinense) Smooth, unspotted stem. 1-5 ft in height. Native to U.S. http://plants.usda.gov/java/profile?symbol=COCH2 Wild chevril (Anthriscus sylvestris) - not sure if that's naturalized in the USA though) Yes, it is in Pa and other states http://plants.usda.gov/java/profile?symbol=ANSY Height: 1 to 4 feet on average but can grow over 6 feet tall Stems: Hollow and furrowed; soft-hairy below, smooth above; fringe of hairs at stem nodes. http://www.agf.gov.bc.ca/cropprot/chervil.htm Hedge-parsley (Torilis arvensis) They grow in a spreading form 2-6 feet in height. Leaves are alternate, pinnately divided, 2 to 5 inches long and may be slightly downy. The stem is usually covered with minute white hairs. http://plants.usda.gov/java/profile?symbol=TOAR
Pay also attention to the bracteoles. In Conioselinum and Torilis they are linear, in Anthriscus - lanceolate to oval and reflexed. As much as I can squint into your picture, the seed umbels have wide reflexed bracteoles which suggests it is Anthriscus.
Has the purple spots at all stages of growth? That is good to know. So far, I've haven't seen a Waterhemlock, but I will keep that in mind. Many of the plants are well over 4 ft tall and average 3 ft, so it's unlikely to be Wild Caroway.
I was able to go back and get a closer look at the plants today. I took some closeups and also cut a stem. There are hundreds of these plants. According to the information provided on this forum, it looks like it's Wild chevril (Anthriscus sylvestris). The stem is definitely hollow. Also the plant has a hairy lower stem, but the upper stem is much less hairy and becomes smoother going up. The attached pictures should be enough to make a positive identification.
My thoughts were Anthriscus sylvestris.. When crushed between the fingers, the leaves produce a strong, almost aniseed-like scent. Cow Parsley has hollow stems. It is slightly hairy. Here are a few links to reliable sites in Britain that may not come up in your searches. First has several pics including a good close up of flowers. Quote from 1st link... "Petals slightly notched or unnotched, outer flowers have outer petals larger, inner ones have all petals same size." http://www.plant-identification.co.uk/skye/umbelliferae/anthriscus-sylvestris.htm http://www.dgsgardening.btinternet.co.uk/cowparsley.htm http://www.thepoisongarden.co.uk/atoz/conium_maculatum.htm http://commons.wikimedia.org/wiki/F...escence,_May_2008,_Prague,_Czech_Republic.jpg. http://www.torrens.org.uk/FFF/plants/CP+H.html http://www.naturespot.org.uk/species/cow-parsley http://wildplants.files.wordpress.com/2010/05/cow-parsley-leaf.jpg . Hope this helps.
Thanks, lots of good information on the links. No they didn't turn up on any searches I made. Interesting info about the size difference between outer and inner flowers; I didn't notice that. The third link, http://www.thepoisongarden.co.uk/atoz/conium_maculatum.htm, is really good in comparing Poison Hemlock to Wild Chevril side by side. It's remarkable how similar they are - except for the red splotches and height of course. I can see how someone can mistake one for the other. This is especially important since Wild Chevril is edible. This was really a good learning lesson in making sure to provide clear and complete information to get a positive plant ID.
Last link.. This was a site I use regularly, and trust, but I couldn't find it just now! Superb set of 10 images. http://www.floralimages.co.uk/page.php?taxon=anthriscus_sylvestris,1&ad=2
I must admit that the sources provided are of a much higher quality than those I was looking at. An important quote from http://www.thepoisongarden.co.uk/atoz/conium_maculatum.htm: "Conium maculatum is another plant which was said to have been speckled by Christ's blood as it grew under the cross. This may be because the speckles are not visible on the young plant and could be thought to appear at Easter to coincide with the crucifixion." So it appears that Poison Hemlock's red splotches are not always present for all stages of growth. Very important information. Thanks
SS Thank you very much for the excellent sites you provided. I book marked them. I had no idea there were so many look alikes with such diverse effects. The 55 yr. old that ate the salad was here in Anacortes if I remember correctly. That is what got some of us checking into these plants. We seem to have most of them lurking on own roadside.
Safe to exclude Conium maculatum, as that has more yellow-green, 'lush'-looking foliage (very distinctive, very different from your plant).
True, but wouldn't that apply assuming familiarity with both species? The same site also notes this: "Other than being slightly more shiny and a brighter green colour, there is little to distinguish between the leaves and, certainly, if only one of the plants is available identification would be difficult."
