Stopping weed spread at harvest: Tips and tricks

We all love the sound of harvesters firing up, signalling the start of harvest! The sound of those harvesters coming to life across our region should also be a reminder that it is also prime time toproactively stop the spread of weed seeds across and between paddocks that harvest season can bring.

New and herbicide-resistant weeds can spread quickly as harvest machinery moves between paddocks and farms. With a little planning and good harvest hygiene, growers can significantly reduce the risk and protect future productivity.

Harvest weed spread hit list:

✅Plan ahead to limit weed spread
Prioritise harvesting weedy paddocks while weed seeds are still attached and can be captured. Within those paddocks, harvest the cleanest areas first before moving into more heavily infested sections.

✅Clean down machinery between paddocks and farms
Adopt a "come clean, go clean" approach for machinery, seed and fodder. Thorough clean-downs can help prevent the movement of new and herbicide-resistant weeds across properties.

✅Use harvest weed seed control (HWSC)
Harvest weed seed control offers a valuable opportunity to reduce weed populations by preventing weed seeds from returning to the soil seedbank. By capturing, concentrating or destroying weed seeds as they pass through the harvester, growers can reduce future weed pressure and slow the development of herbicide resistance.
There are a range of HWSC options available, from lower-cost methods such as chaff lining through to seed impact mills, which can destroy more than 90 per cent of weed seeds contained within the chaff fraction.

✅Access more tips and resources
For practical guidance on harvest hygiene and weed seed control, visit the GRDC website to read the full article and explore additional resources.

Agronomists emphasise that harvest weed seed control is most effective when used as part of an integrated weed management program that includes crop competition, strategic herbicide use and careful paddock planning. Over time, this consistent approach can significantly reduce weed seedbanks and improve long-term weed control outcomes.

For growers looking to strengthen their weed management program, harvest hygiene remains one of the simplest and most effective tools available to protect productivity and reduce the spread of problem weeds.