How to Choke out Thistle and Other Invasive Weeds

Q: We recently moved to a two-acre parcel that has a lot of thistle on it. Could you please tell me the best way to get rid of this plant?

There are different “Thistle” (Cirsium spp.) in B.C. Most tend to be an introduced weed usually with a long tap root. Plants can easily regenerate from small roots and from seeds.

Due to the large area in question there are several possible solutions. Continual mowing right to ground level could weaken the thistle. Using heat, like from an infrared burner powered by propane, can damage the weed enough to weaken it (see On grass areas, overseed with appropriate grass blend to choke out the thistle on a regular basis, or use thick mulch, such as bark mulch, to smother out the thistle. Or, if all else fails, use a systemic herbicide as directed on the packaging.