Sustainability quest propels almond R&D agenda

For anyone wanting to know just how seriously Australian horticulture views the importance of sustainable production, they need look no further than the nation’s almond industry.

The almond industry long ago recognised that sustainability was not just a hollow buzz word but in fact a guiding principle in its quest to cement a vibrant future for its growers.

Sustainability is very much at the core of the industry’s research and development investment agenda, according to Hort Innovation head of sustainability research and development, Kathryn Young.

“It is an industry priority clearly set out in the Almond Strategic Investment Plan (SIP) 2022-26 which is a roadmap to guide Hort Innovation’s investment of almond industry levies and Australian Government contributions,” Ms Young said.

“Supporting sustainable orchard systems through an integrated approach focused on plant improvement, orchard productivity, soil health, water use efficiency, pollination, insect pest and disease management, and emerging technologies is the industry’s highest priority, as detailed within the SIP.

“This industry priority is the catalyst for Hort Innovation continuing to invest – on behalf of growers – in a suite of R&D programs employing innovative technologies and approaches to equip growers with new knowledge and tools to bolster their sustainable farming practices and long-term viability.”

Whole orchard recycling is the focus of one of the investments that sits under the ‘pathway to carbon neutral’ project theme umbrella.

The project is quantifying the impact of whole orchard recycling on the carbon footprint of an almond orchard, including the impact on carbon storage and turnover in the soil, soil greenhouse gas emissions and carbon accumulation by newly planted trees.

The information gathered through this project will support almond growers to integrate whole orchard recycling into their orchard redevelopment programs by demonstrating the potential of carbon farming, changes in soil health, irrigation use efficiency and productivity improvements.

Delivered by the South Australian Research and Development Institute (SARDI), the project is assessing any co-benefits from orchard recycling such as more rapid orchard establishment, as well as potential negative impacts such as increased pressure from soil pathogens and potential for nitrogen draw down.

Almond trees accumulate significant amounts of carbon through their trunks, branches and roots during their lifecycle. When an orchard reaches the end of its commercial life, this resource is traditionally managed through burning as part of the orchard redevelopment.

While burning rapidly clears debris from the site and can reduce pathogen load, it also releases a significant amount of carbon that could potentially be sequestered or at least incorporated to improve soil organic matter and fertility, and help with the establishment and productivity of the new orchard.

The alternative to burning prior to replanting is pulverisation of the perennial portion of the almond trees and incorporation into the soil prior to replanting (known as whole orchard recycling).

Victorian grower Neale Bennett first saw whole orchard recycling in action in California in the United States some years ago when attending a conference where the multiple benefits of incorporating mulched tree matter into the soil were reported.

“While a couple of growers here in Australia have been mulching one or two rows of old trees, until now there hasn’t been any scientific measurement of the effects on water retention, soil structure, organic matter and carbon levels,” said Mr Bennett, whose family-owned and operated orchard at Merbein is hosting trials for the whole orchard recycling project.

“We need to prove to industry and the wider community that this practice is a viable alternative to burning. We want to grow almonds in an environment where we’re focusing on waste reduction, improving water usage and improving nutrient application and uptake – not just for the benefit of our production systems but also because that is what society is asking for.

“We are already doing that to a large extent – for instance, we’ve moved from 95 per cent sprinkler irrigation to 99 per cent targeted drip irrigation – but this research will hopefully enable us to magnify our sustainability efforts and the positive impact,” Mr Bennett said.

Another ‘pathway to carbon neutral’ project being funded through Hort Innovation is focused on life cycle analysis in almond orchards.

Led by Edge Impact, this project is undertaking a life cycle assessment of the almond production at the industry level, with the intention of identifying sustainable practices in the industry and reducing the production of carbon emissions. This will be executed through:

• Developing future greenhouse gas emission reduction initiatives
• Raising awareness across the industry of its footprint
• Developing the capability of the industry to undertake future assessments
• Helping to position the industry for domestic and international opportunities that may arise from becoming carbon neutral and in the generation of carbon offsets.

Exploration of cover cropping as a management practice in Australian almond orchards is the subject of another Hort Innovation investment.

The cover crops for soil health and productivity project, led by the University of Adelaide, is assessing the efficacy and practicality of cover crops in specific almond-growing regions for more effective and sustainable orchard management.

The research is seeking to understand how cover crops influence every aspect of the production system and which crops are best to mitigate soil damage, minimise water use, encourage pollinators in the orchard and avoid the need for herbicide addition.

The newest project in the almond industry’s repertoire, ‘Enabling the pathway to best sustainable management practices’, will assist and empower the industry in understanding sustainability risks and support the longevity of Australian almonds as a sustainable, profitable and well-respected industry.

This project utilises Growcom’s purpose-built sustainability benchmarking platform, building modules as Almond Hort360. The project will provide the Australian almond industry with a foundation to approach sustainability in a targeted and industry-specific way.