Hefting or Learing
Hefting and learing are the terms used to describe the settling and acclimatising of a flock of sheep to a particular part of a common. Hefting or learing is most frequent on commons in the upland areas of northern and southwest England.
The way in which sheep become hefted is complex but probably results from a combination of factors including:
Grazing livestock have a natural tendency to stay together, especially in family groups.
Lambs learning from their mothers which area of the common they graze when they are turned back onto it after lambing
Hefted flocks being bred on the farm from generation to generation, possibly creating a genetic disposition to hefting. Sheep from another area will usually only be introduced onto a common to form, or become part of, an existing hefted flock, if there has been disease or another problem with the earlier flock, or grazing is being reintroduced.
Farmers will shepherd their flock to graze within the area traditionally regarded as the heft of their farm, often bordered by physical features such as ridges and streams. Farmers will also gather the sheep back to the farm the same way every time; part of hefting is knowing the way home.
The pressure of sheep grazing contiguous areas at similar stocking density will hold adjacent flocks to their heft.
It is important to understand the importance of hefting/learing to the management of a common, and the impact of different actions on the equilibrium of the hefted flocks.
For example, significant stock reductions on one area of a common - resulting in a marked difference in stocking density across the common - is likely to result in a movement of hefts as sheep naturally move into areas of lower stock density with better vegetation. It is therefore important to take a global approach in order to avoid actions on one part of a common impacting on another area.
A significant reduction in stock on a common may well result in larger, healthier ewes becoming more predisposed to give birth to twins (because of improved nutrition). Twin lambs are usually turned back onto the common with their mother later than single lambs and have less time to “lear” the heft from her.
Hefting also relies in part on the shepherding of the farmer. As the number of hill farms has reduced, the amount of shepherding carried out on common land has fallen. In some areas, this has contributed to a breakdown of the hefting system.
The impact of a failure of hefts should not be underestimated. Farmers will have to devote more time to gather their disparate flock and to collect sheep that have been gathered from adjacent hefts. Whilst these hefts may be adjacent, the farms with which they are associated may well be on different sides of a watershed and many miles apart by road.
The importance of hefting is reflected in the fact that, if the enclosed land associated with a hefted flock is sold with its appurtenant rights, then the hefted flock will normally be conveyed with it. Agricultural law requires that at the end of a tenancy, tenants must be compensated for the increased value of each ewe forming part of a hefted and acclimatised flock.
Acclimatisation means that sheep are able to cope with the mineral deficiencies of the area, the weather and ticks, if they are present. They will also know where to find water and shelter. Many landlords in upland areas own part of the hefted flock as a way of safeguarding against the loss of the entire flock in the event of bankruptcy of a tenant; such a flock is known as a landlord’s flock and will typically comprise about one third of the total flock.