Controlling Extreme Weeds After Extreme Events

Summary

​The aim of this Producer Demonstration Site (PDS) is to demonstrate to what extent improved weed control and follow-up management (eg: grazing, fertilizer or additional chemical control) improves both persistence and productivity of newly sown or degraded permanent pastures in fire affected areas. 

Objectives

By December 2025, in the Upper Murray and East Gippsland regions of Victoria the consultant and producer group will have:

1. 90% of core and 45% of observer group members more confident in identifying key pasture and weed species by;

   • Weed and pasture identification field day (late Autumn 2022)

   • Pasture assessment tools to estimate weed percentages and pasture composition

2. Assessment of appropriate interventions and control strategies

   • Autumn weed identification and control recommendations field day, and these recommendations implemented, on a host farm in each region (June 2022)

   • Development of long term weed control strategies for the 4 host farms.

3. Implement up to four different weed control strategies on newly sown pastures at demonstration host farms using a combination of approaches that include; chemicals, fertiliser and tactical rest periods, that result in a 20% higher desirable plant species by Spring 2025 (three years after sowing).

   • Undertake pasture benchmarking to establish priority weeds.

   • Implementation of individual weed control programs on host farms.

4. Implement two different weed control strategies on demonstration host farms, in consultation with lead agronomist, that result in a 10% improvement in desirable species in previously degraded but not resown pastures by Spring 2025.

5. Achieve a 50% increase in the number of observer producers of the two regions doing annual assessments of key weed species and a winter assessment of pasture composition across key paddocks by 2025.

6. 90% of core producers and 40% of observer produces indicate they have adopted or intend to adopt at least one of the weed control management practices implemented at one of the demonstration farms into their own property.

Progress

‘Controlling Extreme Weeds After Extreme Events’ is a relatively new PDS in the fire effected regions of Upper Murray (UM) and East Gippsland (EG). 

Four host farms have been selected and are implementing a range of interventions to achieve more productive pastures on-farm.

Group members have been surveyed to assess their knowledge, skill, and attitudes towards weed management on farm and are interested in learning how grazing management and soil fertility can complement chemical weed

The Producer Demonstration Site (PDS) ‘Controlling Extreme Weeds After Extreme Events’ in the Upper Murray and Gippsland has started to implement management strategies to increase pasture productivity.   

Key management strategies include; use of custom fertilizer blends to address potassium deficiencies, use of fertilizer on previously unfertilized native pastures, fertilizer applications based on soil testing the poorest parts of a pasture, winter cleaning of broadleaf weeds prior to establishment of a perennial pasture, tactical use of grazing to manage spring residuals to promote tillering and use of extra knockdown chemical applications when sowing annual crops to do a paddock clean.   

Data collection to assess pasture composition, quality and quantity has commenced - although at this early-stage differences have been small and have tended to be a factor of timing of sample collection in relation to grazing of paddocks, as opposed to differences in pasture growth rate or production.  Upcoming activities include collection of summer pasture data and an information session on ‘The role of grazing management in weed control’ and a weed identification and sprayer calibration day.