Plantstones' could help lock away carbon
05 January 2008
Rachel Nowak
Magazine issue 2637

ONE way to cut greenhouse gas levels in the atmosphere may be to exploit a particular talent some plants have of locking away carbon. All we need to do is choose the right strains of crops to grow, and they will sequester carbon for us for millennia.
That's the idea of two agricultural scientists in Australia, who say the trick is to grow grasses such as wheat and sorghum, which lock up large amounts of carbon in so-called plantstones, also known as phytoliths. These microscopic balls of silica, which form around a plant's cells as they take the mineral up from the soil, may help to strengthen the plant and protect it from disease.

As phytoliths form, they also lock up carbon by trapping scraps of plant material. They are practically indestructible, so once the plant dies they enter the soil where they may sequester carbon for thousands of years...