They both mean the same thing, though "heritage" is usually used to describe animals while "heirloom" refers generally to kinds of plants. These terms describe varieties of animals and crops that have unique genetic traits, were grown or raised many years ago, and are typically produced in a sustainable manner.
Heritage animals have been bred over time to develop traits that make them particularly well adapted to local environmental conditions. Heritage breeds are generally better adapted to withstand disease and survive in harsh environmental conditions, and their bodies can be better suited to living on pasture.
Heritage breeds also serve as an important genetic resource, and when heritage breeds become extinct, their unique genes are lost forever and cannot be used to breed new traits into existing breeds. By raising heritage animals, we are helping to preserve valuable traits within the species so that future breeds can endure harsher conditions.
Heirloom fruits and vegetables are unique plant varieties, which are genetically distinct from the commercial varieties popularized by industrial agriculture.
By growing heirloom fruits and vegetables, we are helping preserve genetic diversity by ensuring that these unique varieties are not completely replaced by the few commercial varieties that are mass-procedured by industrial agriculture. We will produce delicious, unique, and interesting kinds of fruits and vegetables, and grains that add color and flavor to meals that everyone can enjoy.
Baker Heritage Farms does not plan to join the "organic" movement, which appears to be more of a source of income for those that certify such farms; however, by following Good Agriculture Practices as well as the standards set by the organic movement, we will be able to comfortably and honestly provide "all natural" fruits, vegetables, grains, and livestock.