ANN ARBOR, Mich., April 16 (UPI) -- Two Michigan Girl Scouts say they won't sell cookies after learning the production of palm oil is threatening the habitat of endangered Indonesian orangutans.

Twelve-year-olds Madison Vorva and Rhiannon Tomtishen learned while doing research for an award project that palm oil used in Girl Scout Cookies is produced in rainforests that used to be inhabited by orangutans, The Ann Arbor News reported Wednesday.

To grow the fern-like plant that produces palm oil, trees in the rainforest are cut down and then the entire area is set on fire.

The girls say deforestation is spreading rapidly as the demand for fat-free palm oil rises.

Because their project is aimed at raising money to save the orangutans, the girls said it would be counterproductive to sell a product that uses palm oil.

"We've seen pictures of orangutans set afire and beaten," Madison told the newspaper. "You really want to reach out and do all you can to help save them."