‘Encouraging results’: Early studies point to benefits in growing native saline foods in the Wheatbelt

Growing salt-tolerant bush foods on degraded land in the Wheatbelt could have a ream of long-term environmental benefits, according to researchers. The results of a 2019-21 study at Badgebup farmer David Thompson’s property — where he is working with gourmet food supplier Lance McLeod and Katanning Landcare to commercialise the plants — have boosted confidence in the project’s environmental goals. Early results found a plantation of salt-tolerant species reduced the salinity of the soil and increased pH, with more benefits anticipated down the track. Soil scientists Dr Jolene Otway and Dr Bede Mickan hope it could “revolutionise” the way more than two million hectares of salt-affected farmland is used across the State. The project monitored the soil health, groundwater and plant health at two sites on the Great Southern farm. In the pairs’ report — Environmental Reporting for Saline Bush Foods Production – Soil, Water and Habitat — they said while short-term results showed the “detrimental” impact of tilling in preparing the plantation had not been recovered, the overall trajectory was positive. “The outcome of this study has highlighted the conflicting interest within the short term of a saltbush regenerative program coupled with a saltbush harvesting program on ecological systems,” it read. “Long-term however, it is anticipated that salinity indicators will reduce and, with light harvesting, the soil carbon and available mineral content as well as the above ground coverage and vertical habitat creation will increase. “In turn this will provide ecological and environmental benefits potentially in excess of that present prior to the project.” The Plantation site was a “salt scalded” 200m x 80m bare area north of a saline drainage area between two broad acre cropping fields, which were planted to saltbush in 2019. The Wild Harvest site was in a lower lying saline drainage area with existing ice-plant, samphire and pigface used for wild harvest, which was scarified — scratched to promote plant growth — using a tractor mounted rake in Autumn 2020. A non-scarified area was also left to serve as control. In the Plantation site, pH levels increased eight per cent, while nitrogen, carbon and salinity levels decreased. Plant coverage also increased 17 per cent. Carbon and pH remained relatively consistent in the Wild Harvest site, while nitrogen increased 12 per cent and salinity indicator — electrical conductivity — increased by 39-602 per cent from 2020-2021. Between greenhouses and “wild harvest” areas, saltbush, samphire, ice-plant and karkalla are all grown on the Great Southern property and packaged up for retail suppliers and chefs across the country under the brand Moojepin Foods. Katanning Landcare officer Ella Maesepp said the concept of the project — which began in 2017 and was funded by the Australian Government’s Smart Farming Partnerships program — was exciting from both a farming diversification and environmental perspective. “The concept was exciting, as there is the assumption that actively managing and farming these lands with native species would help to improve the degraded condition of those soils,” she said. To investigate just what impact the foods had on the soil, scientists Jolene Otway and Bede Mickan were called in to monitor changes in soil carbon, soil microbial activity, organic and inorganic compounds, groundwater and arboreal habitat as a result of the growing systems. While the time frame for monitoring an ecological system was short, Mrs Maesepp said the results were heading in a positive trajectory. “It gives us further confidence that encouraging saline bush foods production for the gourmet market has positive environmental outcomes,” she said.