organic control of Canada Thistle

by judith
(Billings, MT)

What is the most effective way over time to get Canada Thistle out of a grass coverd burm with Aspen the top canopy, snowberry and roses the understory?

Doug says you can spot spray Canada thistle with a 7% pickling vinegar (NOT regular vinegar) and this will burn it off. You'll have to repeat this at regular intervals.

Note that adding two tablespoons of a vegetable oil and a dash of liquid dishsoap makes it work much better (the soap is critical for success)

Repeat the spray every time the plant starts throwing new shoots or greening up. It will take muliple sprays to kill this plant.