The beginning of a green end is at hand for barren moonscapes left by oil sands mining. Super alder shrubs bred by the National Research Council are ready to sprout where no plants have grown before.

In tests of the budding green power, within three years the bushes grow enough for their leaves to brush helmets worn by workers who plant them behind security fences in gray-black tailings sand piles. Underground, the bushes perform a miracle by giving birth to an invisible, self-sustaining universe of microscopic crops, grazers and predators called the rhizosphere.

Toughened up alder shrubs have turned in stellar performances since field trials began in 2005 at Syncrude Canada Ltd., reports Charles Greer, the NRC’s Montreal-based environmental microbiology group leader. The first large crop will be sown this spring.

About 6,000 super alders are ready to be planted at up to three potential sites at Suncor Energy Inc.’s Fort McMurray operation, Greer says. Parts of the mega-mine, which launched the Alberta oil sands industry in 1967, have advanced through enough land reclamation steps that they’ve qualified to enter the biological remediation stage.

Like Suncor, Greer’s plants are pioneers. The vegetation program uses strengthened versions of two alder varieties which are native to the northern boreal forest and lead its growth. In the life cycle of the woods, the species is the first stage and stays to serve as an engine of regeneration after disasters like fires, floods and volcanic eruptions.

Also known as a “primary successor” plant that prepares the environment for bigger and slower-growing leafy or evergreen trees, alders works their wonders by forming a symbiotic relationship with a microbe named Frankia. This is a “nitrogen-fixer” bacterium which takes the most common element out of the atmosphere and combines it with other materials into nutrients.

Alder bushes provide Frankia with a home in the form of nodules or colonies bulging around their roots, plus other materials the bacteria need to thrive. The microbes return the favor. Resulting chemistry magic includes converting or decomposing nasty substances – such as hydrocarbon residues leftover from oil sands separation – into harmless or even useful materials for all living things.

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