Can someone tell me what this is? I've got a TON of this on a new property I just moved to.
Located in Dayton, Ohio, USA
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Sign up to join this communityCan someone tell me what this is? I've got a TON of this on a new property I just moved to.
Located in Dayton, Ohio, USA
Definitely in the Apiaceae Family. I considered Anthriscus sylvestris (called cow parsley or Queen Anne's Lace) at first, but looking at it a bit more, I'm pretty sure it's Conium maculatum (Hemlock). Fortunately I found a website discussing the differences between the two. From what I can see in your pictures the stems appear rounded rather than grooved, suggesting Hemlock. Also the red dots on the stem are suggestive of Hemlock.
I would suggest clearing it out CAREFULLY before it flowers. Wear gloves and a long sleeved shirt so the sap doesn't get on your skin, if it does wash it off fast. The sap has the potential to cause localized burning/rash on your skin, but it's only lethal if you eat it.
The University of Missouri identifies it as poison hemlock (Conium maculatum L.). Look here - - http://ipm.missouri.edu/IPCM/2012/2/Weed-of-the-Month-Poison-Hemlock/
I agree that this is Conium maculatum, poison hemlock. The big tip-off for identifying it is the purple spotted stems, which if you look closely also have a glaucous (whitish-waxy) coating, and are not hairy. Contrast with other similar-looking species like carrot / queen anne's lace (Daucus carota) which has hairy stems and usually lacks the purple spots. Also notice the multiply-compound leaves that are fine-textured and kinda fernlike. Although I do not recommend touching it with bare hands, it also has a distinctive and unpleasant smell.
In North America it is an invasive plant, and it is also highly toxic. I would recommend removing it but urge caution.
Removal is doable but safety precautions are important; although it does not usually cause contact dermatitis in small amounts, the toxin can be absorbed through the skin and I think there is at least one case of a fatality involving exposure through trying to weed it. I have worked with it extensively and I always limit my work to a dry day, cover up fully, long sleeves and gloves, and limit the amount of time I spent with the plant to a half hour at a time, to be safe. It is probably also best to wear a mask, according to the Purdue University Extension.
Except in the hardest, most compacted soils, it is generally easy to uproot, using a large shovel for the largest ones or just a hand trowel for most plants. It usually grows in moist, rather deep soils where it is easy to remove.
It is a biennial, and I find its long-term persistence in the seed bank is low, so if you remove all flowering plants, there will be less of it the second year, perhaps a few plants the third, and it is often gone after that point except for isolated plants which might be re-colonizations from distant populations. I have had good luck permanently removing it from a site and having it not come back at all after about 3 years.
The easiest time I've found to remove it is right before it flowers, as you can grab hold of the stem. However, the plant is more toxic around this time; it may be safer to remove earlier in the season if you can catch it when it's smaller, and especially it is best if you can spot the first-year plants that just have a basal rosette, and pull them out with a trowel.
If you want to replace it with a plant in the same family but that are safer to have around, and locally-native, you can look at Thaspium trifoliatum, and perhaps Zizia aurea. Both of these are native to your area, I think Thaspium trifoliatum might do a little better. I think they would probably grow pretty well in similar conditions, Thaspium on the drier side of those conditions and Zizia on the wetter side.