Mode of Action
The term mode of action (MoA*) is defined as how a particular herbicide acts on a plant.
Why is it important to rotate MoAs?
Rotating MoAs is important to keep weeds off balance and to reduce selection pressure for resistance to a particular MoA. An even more effective tool is to mix different MoAs in a single application, maintaining full rates of each mix partner, helping to reduce selection pressure for resistance even lower.
Where to find more information about weed management?
A very helpful resource is the Global Herbicide Resistance Action Committee website that contains general information on resistant weeds and their management, guidelines for best management practices and helpful tools such as fact sheets, a global herbicide classification (MoA) lookup, a downloadable poster (World of Herbicides Map) showing at a glance the classification of particular herbicides and others.
*Active ingredients having the same MoA can be grouped and classified together.