J. Cannon, UGA
SAWMILL WASTE makes a good addition to nursery potting mixes, said a UGA horticulturist. Usual nursery potting mixes, on left, don't have much peat, so the sawmill waste, on right, helps add texture and organic matter. Potting soils for home use have composted bark and other organic material already added.
Add another item to the list of recyclables: sawmill waste. A University of Georgia horticulturist is seeing great results using sawdust and pine bark as a growth medium for plants in commercial nurseries.
"We're testing the use of sawmill waste to grow potted plants in nurseries,"said Wayne McLaurin, an Extension Service horticulturist with the UGA College of Agricultural and Environmental Sciences. "What we're using is material that's 20, 25 and 30 years old."
The sawmill waste has been lying around waiting to be used. "It's already broken down, so the nitrogen levels aren't too high," McLaurin said. "You wouldn't want to use fresh sawdust."
McLaurin has also found a few surprises in the decades-old sawmill waste. "It's a wonderful product, but we definitely have to sift it," he said."We've found everything from machinery parts to tin cans in the piles of sawdust."
Early research shows the product to be useful on certain hollies. "We aren't seeing any performance differences between using this product and current pine-bark mixtures," McLaurin said. "It looks like it's going to be a very good product. But we need to continue testing it to see how different plant cultivars respond."
When the research project began in 1997, McLaurin envisioned the product for use in commercial greenhouses. Since then, he has thought of many ways commercial landscapers could use the product.
"We're looking at it for commercial use first," he said. "But if it works well, I'm sure someone will pick up on it and market it for homeowner use."
McLaurin is excited about his newfound recycled product. "We're always looking for new products and new techniques that will benefit the public," he said. "I think this one will be a winner."
(Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.)