What plants does spray-grazing work on?
The technique is most effective on annual broadleaf plants with short seed life, such as capeweed, erodium and dock at seedling stage (Figure 1). Few weed seeds from previous years remain viable in the soil, so preventing seed production for only one year can dramatically reduce the seed left to germinate the next year.
Other broadleaf weeds can also be reduced and prevented from seeding in the year of treatment, however the impact in future years is less. This is because of the residual viable seed left in the soil from previous flowerings, or because the weeds are perennial and eventually recover.
Phenoxy herbicide applied at the label rates has no effect on annual or perennial grasses.