Research Author:

Georgia Reid, AgPro Management

Project Aim

  1. Demonstrate that chaff carts can benefit sheep enterprises by increasing sheep condition and reducing supplementary feed costs, impacting overall farm productivity and profitability.

  2. Foster a better understanding of the use of chaff carts and other sheep management tools such as condition scoring.


Each year, WA sheep farmers are faced with the summer-autumn feed gap, which is essentially a six month drought. Supplementary feeding over this period is one of the main on-farm expenses, and its reduction would directly increase whole farm profitability. It is also a period of time-consuming, stressful monitoring to ensure sheep are receiving adequate nutrition.

The feed gap makes it difficult to maintain sheep condition, and limits stocking rates over summer as there is little feed on the ground. The other significant impact of lack of available feed is on mating ewes’ live weight and nutrition, which is vital for high lambing percentages.

These limiting factors can be eliminated by adequate feed. However, the current solution is expensive, with supplementary feeding, grazing stubbles, and manipulating lambing and joining time. The solution still limits profits and production.

MLA supported Producer Demonstration Sites are up and running in the Great Southern area to further investigate the value of sheep grazing chaff piles during the autumn-summer feed gap. The three-year project aims to show how chaff carts can benefit sheep enterprises by increasing sheep condition and reducing supplementary feed costs; leading to overall increases in farm productivity and profitability.

Trial Details

Trials run in the nearby shires by AgPro Management have demonstrated that grazing chaff carts piles can help reduce the feed gap and therefor improve livestock profitability on mixed farming enterprises. Depositing chaff in piles makes it more accessible to sheep, as well as maintaining its quality for longer compared to chaff spread across by the paddock by traditional harvesting methods. With Sheep being more productive on chaff piles, there is less chance of sheep being underfed and less time needed to be spent hand feeding. The benefit of better utilising a feed source already on farm (a by-product of the cropping system), is an environmentally friendly solution that could reduce feed costs and increase production potential of sheep flocks on mixed enterprises in many regions.

Four properties hosted demonstration sites this year, run by The Gillamii Centre, and members around Cranbrook and Tambellup. Using identical DSEs, ewe mobs were split into a paddock with chaff piles, and a paddock that had been chopped and spread (usual harvest methods). The paddocks at each farm were of the same variety (E.g. zen wheat) and of a similar yield. Canola, barley and wheat stubbles were grazed for six weeks, with sheep weighted and condition scored every three weeks.


Results from the second year of trial showed sheep grazing chaff cart piles weighing between 1.33 kg and 2.88 kg more than those grazing traditionally spread stubbles, with marginally higher condition scores. Sheep gained weight in the first three weeks of grazing (except all treatments at Witham) with chaff pile grazing averaging slightly higher weight gains.

In the remaining three weeks, the sheep lost weight at different rates, depending on the chaff treatment. Those on stubble lost on average 3.29-3.38 kg/hd, while those on chaff averaged losses between 2-3.27 kg in the last three weeks. Across the entirety of the six week grazing period, all sheep grazing stubbles lost weight, and three of the four properties grazing chaff piles saw minor weight increases (averaging 0.1-0.45 kg). This led to the chaff grazing mobs being on average 1.99 kg heavier than those grazing traditionally chopped and spread stubbles. In 2017, this result was 1.74 kg, and in 2016 3.4 kg. This could be due to summer rains or more efficient harvesters, with less thrown out the back.

Feed tests showed the feed to have varying energy levels, with chaff piles recording 5.8-7.8MJ/kgDM and the chopped and spread chaff 3.9-4.5MJ/kgDM. Digestibility averaged 42%, and crude protein 4.4%, with little differences between the paddocks. In 2017, canola residues were of better feed quality compared to the wheat and barley residues, which coincided with the highest sheep gains. This was seen again within the chaff piles in 2018, but not the canola stubbles which could be due to harvester efficiency.


The project will continue for another year, with economic analysis to show the impact of the overall farm profitability. For more information, contact Georgia Reid at or, 0447 523 110.