Daniel Grushkin

A Hidden Cost of Farming (On Earth)


When Don Mavinic looks at cow manure he sees a puzzle in need of a solution. There’s phosphorus locked in there, and the world is desperate for it.

Mavinic is a professor of civil engineering at the University of British Columbia in Vancouver, and he knows that there are three essential nutrients on which all plant life is based: nitrogen, potassium, and phosphorus. The problem is that phosphate rock, the ore from which the mineral is extracted, is in finite supply. Over the past several years, scientists, government officials, and corporations have begun to worry about what will happen when the rock runs out. Though the immediacy of the problem is subject to debate, the need for long-term solutions is indisputable. Mavinic believes that cow pies are the future.