natural behaviors". The term "free range" is mainly used as a marketing term rather than a husbandry term, meaning something on the order of, "low stocking density", "pasture-raised", "grass-fed", "old-fashioned", "humanely raised", etc. There have been proposals to regulate USDA labeling of products as free range within the United States. what constitutes raising an animal "free range" is almost entirely decided by the producer of that product, and is frequently inconsistent with consumer ideas of what the term means. Free-range poultry In poultry-keeping, "free range" is widely confused with yarding, which means keeping poultry in fenced yards. Yarding, as well as floorless portable chicken pens ("chicken tractors") may have some of the benefits of free-range livestock but, in reality, the methods have little in common with the free-range method. A behavioral definition of free range is perhaps the most useful: "chickens kept with a fence that restricts their movements very little." This has practical implications. For example, according to Jull, "The most effective measure of preventing cannibalism seems to be to give the birds good grass range." De-beaking was invented to prevent cannibalism for birds not on free range, and the need for de-beaking can be seen as a litmus test for whether the chickens' environment is sufficiently "free-range-like". The U.S. Department of Agriculture Food Safety and Inspection Service (FSIS) requires that chickens raised for their meat have access to the outside in order to receive the free-range certification. However, what qualifies as "access" is not defined. There is no requirement for access to pasture, and there may be access to only dirt or gravel. Free-range chicken eggs, however, have no legal definition in the United States. Likewise, free-range egg producers have no common standard on what the term means. The broadness of "free range" in the U.S. has caused some people to look for alternative terms. "Pastured poultry" is a term promoted by farmer/author Joel Salatin for broiler chickens raised on grass pasture for all of their lives except for the initial brooding period. The Pastured Poultry concept is promoted by the American Pastured Poultry Producers' Association (APPPA), an organization of farmers raising their poultry using Salatin's principles. This term is not defined by the USDA and has no legal definition. To use a term like pasture-raised, producers must submit documentation to the FSIS of continuous free access to the outdoors, but do not need to include additional terminology