This is how I did it:
- got mastitis
- had HUGE cravings for orange juice
- sent Mom to grocery store
- drank juice and read carton while eating lunch
- read that by visiting www.tropicanarainforest.com and entering the code on my carton Tropicana would save 1oo sq feet of rainforest.
You don't have to do the first three steps; I strongly urge you to not even attempt the first.
You do have to set up an account and give them your email and mailing address, which might mean mail, which might mean less trees anyway, but we can pretend we know that those coupons they're mailing us are printed on 100% recycled paper and will be recycled again once used / received.