From the CO2Science archive: Fagopyrum esculentum or Common Buckwheat is a knotweed, though it is not a weed, nor for that matter is it a kind of wheat. Technically it’s not even a cereal. But buck up because it is, like other plants, a fan of CO2. In 2007 there were 3 experiments showing that an extra 300 ppm CO2 in the air improved buckwheat growth by an average of 17.3%. So fire up the griddle and make yourself a stack of pancakes because there will be lots of buckwheat in the years ahead.