The Sheep

Each skein of yarn begins life as the wool of a sheep. A sheep which roams the countryside, releasing staggering amounts of methane. Sheep flatulence is New Zealand's primary producer of greenhouse gases. An individual sheep's fart may be a trivial event, but the collective effect is impressive.

According to an article published in the scientific journal Global Change Biology¹, each sheep produces an average of 19.5 mg of methane per 24-hour period. (Scientists have found that the sheep's diet has no effect on methane production.) That's 71.175 grams of methane per sheep per year.

Most sheep are shorn once a year, producing a raw fleece that weighs about four kilograms.

At one fleece per sheep per year, each raw fleece (weighing four kilograms) is responsible for 71.175 grams of methane per year, or 17.79 grams of methane per kilogram of fleece.