A new use for retired wood: Feed the residents of a worm farm

What happens to an apple tree when it has finished its productive life? For many orchards, that wood is burned to make way for fresh plantings. But Wenatchee, Washington-based CMI Orchards transforms its retired wood into a new resource that they believe can replenish the soil.

“Chipping trees instead of burning them means we’re ensuring the tree’s life cycle is carbon negative,” said Rochelle Bohm, vice president of marketing at CMI Orchards. “Throughout the whole farming operation, we are putting about 4.5 tons of carbon back into the soil. Every single day.”

Regenerative farming, repurposing waste

CMI Orchards, one of the largest growers of apples, pears and cherries in the Pacific Northwest, is part of a century-old growing group made up of four families. One of these families is the Allred family, co-owners of Double Diamond Fruit in Quincy, Washington.

In addition to Double Diamond’s apple and cherry orchards, the Allred family also owns Royal Family Farming. Royal Family Farming operates as one of the largest regenerative farms in the United States, often repurposing the waste products from other members of the growing group.

“Royal Family Farm processes all of the waste and byproducts from fields, row crops and orchards,” Bohm said. “The ultimate goal is to keep farms sustainable and produce nutrient-rich crops into the future.”

CMI Orchards, in partnership with Royal Family Farming, opened the Center for Soil Science earlier this year. CMI began working with RFF about five years ago, but regenerative farming has been Royal Family’s focus “for decades,” Bohm said.

“A lot of farmers naturally adopt regenerative practices because they make sense. But the Allred family took it to the next level and are one of the first full models of regenerative agriculture at scale,” Bohm said. “They are doing this for the good of farming and the future of ag for everyone.”

Austin Allred, owner of Royal Family Farms, visits an orchard. Credit: Royal Family Farms.

Millions of worms make nutrient-rich soil

Chipped wood from CMI’s orchards feeds millions of worms in Royal Family Farms’ soil. Liquid waste, produced from Royal Family’s herd of cows, rains down on the repurposed orchard wood. The worms—estimated at more than 50 million wrigglers— break down wood chips and other compost, converting into beneficial worm castings. This nutrient-rich soil is then reused in orchards and fields.

As the worms reproduce every 60 days, The Soil Center needs more and more wood to satisfy the residents of the 8-acre worm farm.

“If we weren’t using apple wood we would have to source wood elsewhere. We use 2,000 acres of wood a year to feed these worms and we need about another 750 to 1,300 acres of wood from other wood sources in order to feed them,” Bohm said. This voracious need for wood waste provides a useful way for trees to continue to contribute to our ecosystem, whether they produced fruit or something else. The Soil Center also receives wood from forest service projects, Bohm said.

“At the end of an orchard’s life or when you’re switching out varieties, all of the good from that tree’s life goes up in smoke,” Bohm said. “As we open this up to others, it gives farmers another way to get rid of wood.”

Credit: Canva

When The Soil Center opened in March, its goal was to distribute soil amendments to its partners by the second quarter of the year. Austin Allred, owner of Royal Family Farming, reported that goal is on track.

Biochar, a black carbon soil amendment made from charred biomass such as wood chips, is already being shipped to fellow fruit growers. The Soil Center has begun experimenting with processes to incorporate biochar into manure and compost, Allred said.

“CMI farmers are taking soil amendments. We are super excited with the results of our biochar so far,” Allred said.

The Soil Center’s early results have its partners cautiously optimistic and looking toward the future. Phase two of the plan includes supplying the wider agricultural community with RFF’s soil amendments. At phase three, an everyday customer would be able to walk into a big-box store and pick up a bag of regenerative soil amendments, Bohm said.

For now, Allred said he is closely watching his blends and waiting for one or more seasons to compile effective data. However, his part in the regenerative movement is on his mind.

“It’s so exciting to be able to have a real, scaled solution to reduce burning across the state and, in turn, have soil amendments that can help us thrive locally,” Allred said.

A focus on soil and capitalizing on the regenerative buzzword could be the vehicle agriculture needs to discuss long-term sustainability, Bohm said.

“There’s a lot of excitement around soil products being the vehicle around telling the regenerative story,” Bohm said. “These are new channels we have to establish as apple, pear and cherry growers. That’s the highest likelihood of raising revenue.”