Environmental movements: Singer tells the Global Warming College Tour to limit use to one square normally, two to three squares on 'pesky occasions'

"All I wanna do is have some fun," sang Sheryl Crow once, but it appears her desires have since changed. Now all she wants to do is limit the use of toilet paper to one sheet per visit.

The singer made her declaration in an article for the Huffington Post to help promote her Stop Global Warming College Tour, an 11-date tour explaining the perils of global warming to Americans. Accompanied by Laurie David, activist and wife of comedian Larry David, the pair have been criss-crossing the country in a biodiesel-powered bus spreading the word on the bathroom hygiene of the future.

According to Crow's new strictures, the average person should use "only one square per restroom visit, except, of course, on those pesky occasions where two to three could be required". Further details were not offered as to the precise nature of these "pesky occasions", though "we are an industrious enough people that we can make it work", she insists.

Awareness of climate change has been growing steadily in the US since Vice President Al Gore's movie, An Inconvenient Truth, began to generate publicity for the subject. Crow and David showed clips from Gore's documentary on their tour.

The last stop on the tour, at George Washington University in Washington on Sunday, featured a performance by Crow with country stars Tim McGraw and Faith Hill, as well as Carole King.

Crow's environmental opinions are not limited to toilet paper. She also believes paper napkins "represent the height of wastefulness", while she has designed a clothing line which features a detachable "dining sleeve" that wearers can use to wipe their mouth while eating.