James writes
Crossbow Herbicide is not labeled for use on poison hemlock, so we would not recommend it for that application. It is labeled for use on tansy ragwort at the rate of 2 quarts per Acre. Since this is a biennial weed, the recommend timing for best results is when the plants are in the rosette stage.
For poison hemlock control, you will usually need a product with more 2,4-D. Opti-Amine 2,4-D is labeled for use on poison hemlock.
Answer last updated on: 03/30/2021
