Consumers are increasingly aware of the impact their food choices have on the environment, and sustainable production is becoming an important factor in their decision making when choosing products.

As Australia’s truffle production increases, growers are seeking effective and sustainable practices that meet the environmental expectations of consumers, farming communities, tourists, and the wider community.

Sustainable weed and pest management alternatives for truffle orchard floors are the focus of a two-year research project being undertaken by the Department of Primary Industries and Regional Development (DPIRD) in Western Australia.

The Australian truffle industry is more than 20 years old and is the fourth largest producer of truffles in the world, after the traditional truffle growing countries of Spain, France, and Italy.

The industry is export focused, with approximately 80 per cent of production exported to markets including North America, Europe, the United Kingdom, and Asia. In 2019, Australia exported eight tonnes of truffles, and production is predicted to increase to more than 20 tonnes by 2025.

DPIRD research scientist Rachelle Johnstone said weeds and pests posed a serious risk to truffle production.

“Weeds compete with the truffle host tree, the establishment of the mycorrhizae, and truffle development; and slugs (image below) and slaters (image in headline) are an abundant and widespread orchard floor dwelling pest of truffles,” Ms Johnstone said.

“However, commonly used herbicides are coming under increased scrutiny by farmers, scientists, and consumers, and the efficacy and impacts of softer alternatives on truffle mycorrhizae and production need to be evaluated.”

In spring 2021, DPIRD commenced trials of sustainable alternatives, including a flame weeder, pine oil, and acid-based herbicides.

“The aim is to assess the effectiveness of these management techniques on weeds, as well as the impact on truffle mycorrhiza health and abundance, soil biome, and slugs and slaters,” Ms Johnstone said.

“The efficacy and cost-effectiveness of other pest management options will also be investigated, including creating a pest-free habitat on the orchard floor through weed management, leaf litter removal, and mass trapping.

Truffle growers will be updated on the project through field days, workshops, and a newsletter.

The current Integrated Pest and Disease Manual will also be updated with project outcomes, including orchard floor management options focused on weed, slug, and slater control, and made available to growers.

Ms Johnstone said knowledge gained through the project could be applicable to other horticultural industries interested in using sustainable weed and pest management alternatives to maintain high value markets.

The Applied Agricultural Remote Sensing Centre (AARSC), based at the University of New England, Armidale is collaborating on the project to map the extent (location and area) of all truffle orchards across Australia.

This will provide industry not only with a better understanding of the current size but also where it is expanding in future years. The map provides essential baseline information to support forward selling, marketing and traceability as well as inform decisions for proximity to resources (water, transport and labour), and critically biosecurity preparedness and natural disaster response and recovery.

Mapping for the Tasmanian growing region has been completed and can be viewed in the Australian Tree Crop Map Dashboard. Note, no personal or production information is presented in the national map. The AARSC are now drafting mapping for all WA growing regions.

Stakeholders are encouraged to contribute by completing the Australian Tree Crop Survey and/or provide feedback directly via the Industry Engagement Web App.

Each of these tools (available from the AARSC industry applications website une.edu.au/webapps) supports the contribution of industry and growers and is essential for mapping new and future orchards which cannot be mapped with satellite imagery alone.

The ‘Improved orchard floor management in truffle orchards’ project is supported by DPIRD, in collaboration with the Applied Agricultural Remote Sensing Centre and the Australian National University, through funding from AgriFutures Australia as part of its AgriFutures Emerging Industries Program, and with contribution from Truffle Producers Western Australia Inc.