12/06/2026
Hemlock warning!
Two years ago I found a giant hemlock plant in one of our hedgerows for the first time ever. Since then I have been vigilant as this plant seems to be on the increase probably due to a wetter climate.
At fist glance it looks like cow parsley although it can grow much larger. Similar clusters of white flowers and a feathery leaf although it is a darker green than cow parsley.
If you look at the first two photos (both hemlock) you can see how similar they are to cow parsley.
The main difference is the stem. Cow parsley is ridged like celery and slightly hairy.
Hemlock has a smooth stem with purple blotches as in the third photo.
Hemlock is dangerous stuff. It will kill your horse and you! It’s one of the most toxic plants in the UK. You definitely don’t want it in your field or even worse, in your hay.
The best way to deal with it is not to handle it and spray it with an appropriate w**dkiller. You can get one from B&Q that won’t kill the grass. It’s currently in flower so avoid spraying these and just spray the leaves to minimise harming pollinators.
Then obviously do not graze the area until it is completely gone and rotted away. That might take a year and you need to be vigilant as seeds can continue to develop after spraying.
If you have to remove it, you need full PPE including a face shield as a the sap is runny and easily splashed on bare skin. Pour w**d killer down the cut stem as it can be difficult to remove the roots on bigger plants.
Ideally bag and bin rather than burn but minimise handling where you can.
These plants are on a compound area not grazed by animals but will be eradicated to prevent them spreading.
As most of our area gets ready to cut hay in the coming weeks, now is the time to check your grazing and hay fields. Remember that smooth,spotty, purple stem!
