Keep pastures healthy and productive with spring weed control

Keep pastures healthy and productive with spring weed control

21 July 2019

With longer days and warmer temperatures, daily spring pasture growth rates will soon hit their peak.

But many broadleaf weeds thrive just as much – if not more – in these conditions. So it’s always a good idea to take stock of what is actually growing in your established pastures before spring really kicks into gear.

Are those paddocks full of high-quality, cost-effective ryegrass and clover? Or do they contain less desirable species, like dock, ragwort, thistles or pennyroyal?

A well-timed spring herbicide programme will not only enhance your pasture dry matter (DM) production this season but will help lengthen the life of existing pastures by removing competition for light, water and nutrients.

One of the most common mistakes made with spring weed control is spraying too late. Just because weeds aren’t immediately obvious in the pasture, it doesn’t mean they’re not there.

Spring-germinating weeds can be present under the pasture cover as seedlings and small plants. After the pasture is grazed, they are exposed to sunlight and are likely to then develop to the point where they will severely limit pasture production.

If weeds are left until they mature and flower, in most cases it’s too late. They will be very difficult, if not impossible, to kill.

The three pillars of good spring weed control are:

  • Start looking for spring weeds early, i.e. September
  • Identify the full range of weeds that need to be controlled
  • Select the right product for the job

Proven herbicide options for this use include Baton® 800WSG and Valdo® 800WG. They are specifically designed to kill broadleaf weeds while the plants are still small.

Baton 800WSG is a selective phenoxy herbicide that controls many broadleaf weeds, including ragwort, thistles, pennyroyal and wild carrot in pasture, without major damage to clover.

Depending on the weed species present, Baton 800WSG can be tank-mixed with Valdo 800WG. This clover-friendly flumetsulam herbicide is particularly useful for improving control of buttercups and brassica weeds such as hedge mustard and wild turnip.

Dockstar® is another useful option where docks are the main challenge. However, often farmers want to eliminate other broadleaf weeds along with dock, in which case a new solution is available; a tank mix using a lower rate of Dockstar (two litres per hectare) with Baton 800WSG at two kilograms (kg)/ha. This combination will provide good suppression of dock and other broadleaf weeds with less pasture suppression than Dockstar alone at the full label rate.

For best results with the Dockstar/Baton 800WSG tank mix, leave pasture for two to three weeks after grazing before spraying and apply the mix before dock seed heads have emerged. Don’t add any adjuvants or other products and leave the pasture for at least one to two weeks after spraying before grazing.

For more information on broadleaf weed control in your existing pastures this spring, or if you would like help identifying what weed species are present in your paddocks, talk to your local TSR or visit your local Farm Source store.

Article supplied by Nufarm NZ

®Dockstar and Valdo 800WG are registered trademarks of Nufarm Limited Baton 800WSG is a registered trademark of Nufarm Australia