Australian almond industry trials carbon-friendly recycling as an alternative to burning old trees
Scientists are working with a Victorian almond grower to trial an orchard redevelopment practice to reduce the industry's carbon footprint.
When almond growers decide to redevelop part of their orchard, the trees are often removed and then burnt.
But the industry is now examining the benefits of chipping the trees and incorporating the wood into the soil before replanting.
Merbein almond grower Neale Bennett was in the United States five years ago and saw the process in action.
"With the EPA (Environment Protection Authority) laws over there, they're not allowed to burn," he said.
"By incorporating the wood chips back into the soil, they're getting better water-holding capacity, better nutrient uptake and more organic matter in, but one of the best things is that it's carbon capture. We're not releasing that carbon into the atmosphere," he said.
Hort Innovation and the South Australian Research and Development Institute are involved in a trial on two hectares of Mr Bennett's orchard, after he decided to replace his trees.
"Dead wood was starting to form into [the trees]. There are some newer varieties on the market, which I want to take advantage of. So, it was about time to strike a blow and start the replanting program," Mr Bennett said.
The 30-year-old trees were chipped in February and have been incorporated into the soil.
The area will be replanted in July or August.
"If we can get the benefit out of what we've been growing for 35 years, why not use that resource," Mr Bennett said.
Mr Bennett said soil measurements were taken when the trial started to assess nutrient levels and water-holding capacity, and this will continue over the next 12 to 18 months.
"There are a couple of growers who've tried it, just with one row here and there. But we've never actually as an industry done a measurement, a scientific experiment where we've looked at the whole improvement from go to whoa," he said.
Mr Bennett said the almond industry in California had been willing to share its knowledge about whole-orchard recycling, including the University of California and the Almond Board of California.
"When we were designing this project, we actually consulted with those who had done it over there and got the initial results, and they're confident that it will work here too," he said.
Opportunities for other crops
Mr Bennett said this practice could be used beyond the almond industry as grape and citrus growers also burn their own vines and trees when they are redeveloping parcels of land.
"We add mulch to a garden, so I can't see why it can't be used on a commercial basis with anything, whether it be vines or trees," he said.
"The basic biology is to build up the organic matter to improve the soil."
If the trial is successful, Mr Bennett would like to see government grants to help growers adopt whole-orchard recycling.
"We've already been told we've got to reduce the carbon emissions. This is one way of doing it and getting nutrients back in the ground," he said.
Kellie Hollingworth. (April 4, 2022). Australian almond industry trials carbon-friendly recycling as an alternative to burning old trees. ABC News. https://www.abc.net.au/news/rural/2022-04-04/australian-almond-industry-trials-whole-orchard-recycling/100953922