Fast, cost-effective and efficient undersowing is a useful technique to extend the life of pastures that may be thinning out but are not yet ready for full renewal.
Undersowing also offers a good opportunity to eliminate costly broadleaf weeds that will compromise the quality of your grazing next spring.
Appropriate weed control gives undersown pastures the best chance to grow to their potential in future weeks and months and protects the time and money you invest in drilling new seed.
A key outcome of pasture repair efforts at this time of the year is reviving poor dry matter (DM) production as promptly as possible. You need to ensure any damage or deterioration that has occurred over the past winter, spring and summer does not reduce farm productivity in the coming season.
Hybrid, Italian and perennial ryegrass seed can be used for undersowing, depending on your requirements. Following up with 2,4-D amine herbicides such as Baton® 800WSG or Sprinter® 700DS tank mixed with Valdo® 800WG will control broadleaf weeds such as chickweed and stinking mayweed.
That’s the advice from Cynthia Christie, a Technical Specialist for Nufarm.
She says if clovers are included in the seed mix, the pasture must be fully grazed once before spraying to ensure clover safety.
However, she points out most undersowing is done with ryegrass seed only.
“In such cases, correctly timed weed control can enhance establishment by removing competition for young ryegrass plants. It also helps prolong the production gains undersowing sets out to achieve in the first place.”
Recommended rates are Baton 800WSG at 2.0 kilograms per hectare (kg/ha) or Sprinter 700DS at 2.3 litres per ha (L/ha) in tank mix with Valdo 800WG at 65 grams per ha (g/ha).
Such applications offer broad-spectrum control for the range of weed species likely to be present while not being too tough on present clover.
The best timing for applications is after undersown grasses are grazed for the first time when weeds are exposed and existing clover plants have less leaf area.
Do you have established pastures that don’t need undersowing but still need a clean up before winter?
Thistles, pennyroyal, water pepper, willow weed, ragwort, buttercup and other weeds will germinate under existing pasture covers in autumn, and once paddocks are grazed, they will take off. Now is a good time to kill them because they’re small and susceptible to herbicides. Options include Baton 800WSG or Sprinter 700DS, Valdo 800WG, or Tribal® Gold.
Conquest® is an option for extremely large weeds or species not well controlled by phenoxy herbicides. Conquest severely damages clovers so these may need to be resown in spring.
For more advice, contact your local Technical Sales Rep or visit your Farm Source store.
Important: Many agrichemical products have prolonged milk withholding periods due to the significant food safety risk. Careful management through robust practices and procedures of agrichemicals is required on-farm to mitigate this risk.
Baton®, Conquest are registered Trademarks of Nufarm Australia Limited. Sprinter®, Valdo® and Tribal ®are registered Trademarks of Nufarm Limited.
Article supplied by Nufarm.