The EPA is phasing out the sale of CCA-treated wood over concerns about arsenic leaching from the wood into the soil. However, many structures built from pressure-treated wood remain in yards. What to do about the arsenic in the soil already? Researchers at Edenspace Systems, a leader in phytoextraction -- using plants to extract poisonous chemicals, such as arsenic, lead, and uranium from the soil -- have found a plant that loves sucking arsenic out of the soil.
Edenfern is a southern fern that's hardy to USDA zone 7, grows 2 to 4 feet tall, and is adapted to sun or part shade. When grown in arsenic-contaminated soils, it removes up to 10 ppm of arsenic in 2 to 4 months, accumulating the arsenic in its leaves. The fronds are then harvested and disposed of in a landfill. It also cleans water, making arsenic-contaminated water drinkable in a few days. Space plants one foot apart in contaminated soil. Edenfern most effectively removes arsenic from the upper layers of the soil (6 to 12 inches).
For more information and to purchase Edenfern, check out the Edenspace Web site: http://www.edenspace.com.