What’s better than an attack on weeds? A second one. Come at them with a different strategy and any survivors left over don’t stand a chance, that’s the beauty of the double knock.
Controlling herbicide-resistant weeds is essentially all about double knocks. This can be one herbicide followed by another, or it could be a herbicide followed by a non-herbicide tool (eg. the ‘Canola Combo’ - crop top followed by HWSC). All that really matters is any resistant survivors to the first herbicide are hit with another control measure so that the weeds don’t set seed.
And then there is the double knockdown. Glyphosate followed by paraquat (or paraquat + diquat). Glyphosate resistance is such a big deal it gets its own, specific weed control strategy. Glyphosate is the world’s most important herbicide and nothing else comes close as a low cost, reliable knockdown, so we really need to look after it.