PDS: Optimising Stubble Grazing Strategies in the Great Southern

Summary

The end of the live export market is a major concern for producers in the Great Southern region of Western Australia, where Merino sheep farming is common. However, research suggests that focusing on Merino prime lamb production can boost profitability, especially with increased cropping allowing lambs to graze crop stubbles for high growth rates.

Instead of a "set and forget" approach, prioritizing lambs in a stubble grazing strategy is optimal. Lambs should move between paddocks to maintain growth rates above 140 g/hd/day, and lower priority mobs can graze stubble until weight changes fall to -40 g/hd/day. Despite most producers grazing crop stubbles in summer, fewer than 15% actively manage grazing. Research also indicates that producers may underestimate the grazing potential of their stubbles.

The MLA GRDC Partnership PDS aims to demonstrate the grazing potential of crop stubbles and how, through effective management strategies, they can be utilised to reduce reliance on live export and shift focus toward the more profitable prime lamb market.

Objectives

By May 2028, in the Great Southern region of Western Australia, the project will establish three demonstration sites each year, engaging 15 core producers and 75-150 observer producers to:

1. Using 12 sites, demonstrate the grazing potential of five different crop stubbles over multiple years.

2. Showcase an improved stubble grazing strategy over the summer period to:

a. Increase liveweight (g/ha/day) and condition scores and support the production of prime lambs.

b. Increase grazing days per hectare and thus carrying capacity (DSE/ha).

c. Reduce Supplementary feeding (kg/dse).

3. Develop practical, easy-to-follow guidelines to help producers implement effective stubble grazing strategies, such as grazing until there are fewer than 10 grains per 1/10th of a square meter. Guides distributed to all core and observer producers.

4. Highlight how optimal stubble utilisation can minimise the need for burning or crunching stubbles.

5. Conduct a detailed whole farm analysis to:

a. Showcase the economic value ($/ha) of adopting an active stubble management strategy.

b. Showcase, at a farm level, the increased meat turned off under the active grazing strategy (kg/ha)

c. Address outstanding questions from core producers (e.g. how the economic benefit varies for systems with 20% crop vs. 80% crop or with different sheep breeds such as Dorper, merino etc).

6. 90% of core producers and 50% of observers report an increased understanding of stubble grazing capacity and have implemented or plan to implement an active stubble grazing strategy.

7. For the observer and core producers, host an annual field day and other activities such as a webinar to present demonstration site results and encourage the adoption of key practices.

Progress

Southern Dirt in WA in collaboration with MLA GRDC Partnership PDS project has been operating the project “Optimising Stubble Grazing Strategies in Great Southern” aims to demonstrate the grazing potential of crop stubbles and how, through effective management strategies, they can be utilised to reduce reliance on live export and shift focus toward the more profitable prime lamb market.

This project is being conducted through a series of 8 producer demonstration sites with a minimum of 4 host producers covering the Great Southern Region of Western Australia. 

Three sites have been completed in the 2025/2026 post-harvest period. An overview of results include visual assessment of sheep performance on stubbles was unreliable, highlighting the value of regular liveweight monitoring to guide nutritional management. 

Ewes stocked at approximately 10 DSE/ha were able to graze cereal stubbles for around 4–5 weeks without supplementation before liveweight declined. Feed tests, feed on offer (FOO) and grain counts did not consistently predict sheep liveweight change. 

Early in the grazing period, ewes gained around 100 g/head/day, indicating that prioritising higher-value mobs to graze stubbles first may improve utilisation and animal performance.