New Trial Sites for the K Extension Project

May 30,2024 K Extension Project, Project Update Article, 2024, Projects, RAD2307,

By Melanie Dixon, WMG Mixed Farming Systems Officer

The K Extension project had a successful year in 2023, identifying and engaging 10 growers in the West Midlands Region and completing K nutrient budgets. The 2023 results were presented to growers at the WMG Crop Nutrition Day in April 2024. This event included a discussion about the 2024 trial site design, particularly what crop species would be of most interest to test their K recycling abilities. In 2024, the project will focus more on physical trial sites to apply our learnings from the previous year.

Presenting the 2023 K Extension Project results at the Crop Nutrition Day.

The first of 2 trial sites have been established at the Brown’s property in Dandaragan to evaluate how different crop species will recycle K from depth. In 2023, the deep soil testing conducted revealed that there was an unexpected amount of K at depth (between the 50 – 90cm range), with the Dandaragan site being based on these learnings. Lupin, canola, serradella, and a short and long season wheat will be sown to test the 5 most common crop types in the region. These crops were identified and chosen in collaboration with the host farmer and discussions with the wider WMG community.

The Dandaragan K Extension Project trial site location.

At this trial site there is also a known compaction layer at 40cm. To combat this, the trial will be replicated and deep ripped. This addition to the traditional site will highlight the impacts of the current host farmer practice of deep ripping. It will be interesting, to see the differences in these sites, if any, throughout the 2024 growing season. As we move through the season and complete in-field sampling, we will get a better understanding of how much K the crops can access and how including a deep-ripping treatment can affect this.

A soil core taken at the Dandaragan K extension site – down to 90cm.

The second trial site that the K Extension Project will be following in 2024 is the long-term Summit Fertilizers trial site at the Marriot’s property in Badgingarra. This trial site was established in 2020, assessing the importance of K placement as either MOP or SOP on canola at rates designed to run-down, maintain and build K soil reserves over time. The ability to establish a long-term trial site is not within the capacity of this project, so collaborating with Summit Fertilizers will allow the K extension project to provide more value to our members and those following the project.

A new article focusing on the essential role of potassium in plant health and crop productivity has also just been released on the WMG website. This technical summary helps in understanding the K cycle, the impact of deep-rooted plants on nutrient availability, and the need for further research on subsoil potassium uptake, with insights specific to the West Midlands region.

The K Extension Project is set to have a fantastic year, building on the learnings from 2023 and working to formally investigate K recycling in the region. There will be an increased focus on field-based research and collaborating with industry in 2024. We hope to utilise the K Extension Project to contribute to the body of knowledge that supports farmers in the West Midlands region in making informed decisions that enhance productivity and utilise the resources available.

The K Extension Project is a GRDC-funded project that is evaluating current K management practices in terms of crop productivity across multiple soil types in the region. If you are interested in being involved in this project please get in touch with us, join a WMG discussion group or follow the WMG website project page.