Feral permaculture is a term used by Terry Leahy, an academic at the University of Newcastle, Australia, to refer to permaculture that uses species that naturally grow well in the local climate. Leahy advocates using as many perennial species as possible, to reduce work load. While feral permaculture does advocate using non-native species, it should definitely be restricted to species already introduced to the area - new species run the risk of becoming extremely problematic weeds.