Trials begin to combat increasing soil degradation on Eyre Peninsula mallee seeps

22 October 2020

of mallee seeps on farming land.

Five mallee seep sites on the Eyre Peninsula have been fitted with scientific monitoring equipment under a two-year project supported by the Eyre Peninsula Landscape Board through funding from the Australian Government’s National Landcare Program.

The monitoring equipment at the five sites will allow water table changes at each property to be tracked. The sites have been set up by Landscape Board officers and local farmers with Farming Systems Consultant, Chris McDonough from Insight Extension for Agriculture who brings experience dealing with mallee seeps sites.

“Mallee seeps are a growing issue on the Eyre Peninsula, generally developing as perched water tables above tight clay layers, forming below deep sandy areas that are collecting excess water in localised catchment areas,” explains Dr Chris McDonough.

“They differ from the large scale highly saline creek-line systems that can’t readily be fixed individually by farmers. However, if left unmanaged, mallee seeps can rapidly spread causing water logging, increasing surface salinity and large, unproductive bare scalds.

“This new project will see farmers’ trialing different management strategies to use more water up slope of the mallee seep and plant salt tolerant species on scalded areas to bring them back into production.”

EP Landscape Board Landscape Officer, Sarah Voumard is coordinating this project which came about after a Kimba farmer talked to her about this issue last year. The Board’s Regional Agricultural Landcare Facilitator (hosted by Agricultural Innovation and Research EP) Amy Wright, is also involved with the project delivery.

“After seeing the challenges caused by mallee seeps on the Kimba property and then again on other Eyre Peninsula properties and at field days in the Murray Mallee; I appreciate the need for action to slow soil degradation on mallee seeps which are presenting in dune swale landscapes across our region,” says Ms Voumard.

“Some of the methods being used to reduce the unproductive mallee seep areas include planting strategic strips of Lucerne up slope of the mallee seep, establishing puccinellia on the seep to slow osmosis, adding sand layers to improve saline scalded topsoils and pumping the water out of the seep to use elsewhere on-farm.

“We’ll be trialling all these methods across our five trial sites, which have now been established with soil and water testing, piezometers, soil moisture probes and satellite NDVI imaging.”

During the two year project, farmers and agronomists will be invited onto the mallee seep demonstration sites near Kimba, Rudall and Lock to hear from the farmers how each area has changed over time.

In the meantime, Ms Voumard is encouraging farmers and farm advisors who would like to learn more about mallee seeps, to get in contact.

“There are opportunities during this project for farmers and advisors to see the demonstration sites and meet our scientist, Chris McDonough, who has extensive experience remediating mallee seeps,” Ms Voumard says.

Dr McDonough has been working on a project with the Mallee Sustainable Farming (MSF) Group with promising results so far, developing practical solutions with participating farmers, even bringing some scalded sites back to cropping.

“Recognising mallee seeps early and remediating them is important, before they become unproductive bare scalds” says Dr McDonough.

“Indications from the MSF Group project are that when the mallee seep ground water is at 6000ppm, the soil can be remediated back to cropping provided farmers use practical management strategies to stop the water flowing from the recharge zones. We are hopeful of positive results in this project for Eyre Peninsula farmers.”

During the project, a video will be produced and made available for people to learn more about mallee seeps and remediation options. A guide of options for managing mallee seeps will also be made available to those who are interested.

For further information please contact either Landscape Officer Sarah Voumard in Cleve on 0429 677 604, or Regional Agricultural Landcare Facilitator Amy Wright in Kimba on 0467 004 555.

See our website for more information about the mallee seeps project.

The Eyre Peninsula Landscape Board came into effect on 1 July 2020, replacing the former Eyre Peninsula Natural Resources Management Board.