Waterhemp is a newer weed in Canadian agriculture, introduced to Ontario in the late 1990s/early 2000s. Its newness, however, does not bring novelty, and it’s safe to say that farmers who’ve had to deal with it are already plenty sick of it.
A recent article on the ONspecialtycrops website includes information from a variety of weed management specialists on factors to consider in approaching waterhemp, including: how to identify waterhemp, as it can be difficult to distinguish from green and red pigweeds; areas in Ontario where waterhemp is likely to be; and what makes waterhemp particularly difficult to manage.
Waterhemp began developing glyphosate resistance in the past six years, and in that time waterhemp populations have been found with multiple resistances, including four-way resistance to Groups 2, 5, 9 and 14.
For the full article, visit the ONspecialtycrops website.