Problem is horse drawn ploughs weigh a ton and take skilful handling I watched two shires being set up to pull a plough at Beamish outdoor museum and they took expert handling and the chaps who owned these huge creatures said the average horse could not pull the plough through anything cept like loamy soil, anything wet or heavy clay type soils and normal horses cannot do it.
Chances are that the owners of the few dozen plough horses in the UK will hire themselves out under contract to survivors after TSHTF, just as they did in Victorian times. (course we could always use city folk as slaves to pull the plough, cannot think of anything they would be useful as cept as beasts of burden
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