What is grown must grow through heritage

During the 19th century, pastures held more value than woods. Dividing land at each change in generation would have led to these lands being progressively split up until they lost all value. For this reason, families in the High-Jura found an original legal arrangement to share inheritance without dividing plots of land: “what is grown must grow”. With what is grown being the trees, and what must grow being the grass that is harvested as hay or that is grazed on every year.