A perennial polyculture is a dynamic, self-organizing multi-species community designed and tended to by a farmer to produce food or other yields. While annual crops sometimes are included in the mix, perennial species, those that live for more than one year, predominate. Typically perennial polycultures refer to the plant species however farmers using this approach will typically take into account the interaction these plant communities have with animals, insects, water flow, and other communities or forces. This food production method mimics naturally occurring ecosystems and is of central importance to the concept of Permaculture. This biomimicry leads to robust, resilient, and adaptable growing systems. 

The Land Institute, a non-profit research and education organization located in Salina, Kansas, works to develop perennial polycultures mimicing a prairie system. The organization's purpose is to develop an agricultural system with the ecological stability of a native prairie and the grain yield of an annual cropping system. The Savannah Institute, based in Urbana, Illinois, does comparable applied research to the Land Institute but focuses on the midwest oak savannah as the model ecosystem after which they model their perennial polyculture designs. 

Usage example: (Perennial) "polycultures undergo succession, offer many niches, and play a large role in creating their own structure, as do plant communities and ecosystems" (Hemenway, p.183).

Resources:

Hemenway, Toby.  (2009).  Gaia’s garden: A guide to home-scale permaculture (2^nd ed.).  White River Junction, VT: Chelsea Green Publishing Company. 

Jackson, W. and L.L. Jackson (1999). Developing high seed yielding perennial polycultures as a mimic of mid-grass prairie. In R. LeFroy (Ed.), E.C. Lefroy, R.J. Hobbs, M.H. O'Connor, J.S. Pate, Agriculture as a Mimic of Natural Ecosystems. Netherlands: Kluwer Academic Publishers, pp. 1-37.

Entry: LLH

Checked: UB, IA