Weed management following flooding

With the recent flooding and widespread water inundation; weed spread and establishment will be a risk across the regions.

Damage to pastures and crops may further allow weeds to thrive through lack of competition from desirable plants, and access to paddocks will also hinder ability to identify weeds in a timely manner and apply control methods.

Weed populations will deplete soil moisture and can create a green bridge for crop pests and diseases, like cereal rusts, potentially causing an epidemic in the new season. If allowed to set seed, there becomes an ongoing seedbank population which will germinate under the right conditions and require ongoing management.

Weed spread may occur through:

• seed spread in waterways

• in organic material transferred in flood waters

• soil seed banks with the moisture for germination post flooding

• transfer of seeds in purchased fodder

• in mud and soil attached to vehicles

You can expect to see common weeds for your region, however, also be on the lookout for new weeds which may establish quickly. Ongoing monitoring will be required to determine:

• weed species ID

• establishment pattern or spread

• management plan for control and prevention of further infestations and seedbank build-up

Maintaining groundcover, increasing plant competition when possible and applying other management strategies such as chemical application, manual removal or fallow management may all assist with reducing weeds.

Seek professional advice relating to management strategies, herbicide options and spray rates as required. Always follow label instructions and ensure appropriate records are kept.

If you see weeds or plants you’re not familiar with, your local council Weeds Biosecurity Officers can be contacted for further information.