The British Agricultural Revolution describes a period of development in Britain between the 18th century and the end of the 19th century, which saw a massive increase in agricultural productivity and net output. This in turn supported unprecedented population growth, freeing up a significant percentage of the workforce, and thereby helped drive the Industrial Revolution. How this came about is not entirely clear. In recent decades, enclosure, mechanization, four-field crop rotation, and selective breeding have been highlighted as primary causes, with credit given to relatively few individuals.
Prior to the 18th century, agriculture had been much the same across Europe since the Middle Ages. The open field system was essentially post-feudal, with each farmer subsistence-cropping strips of land in one of three or four large fields held in common and splitting up the products likewise.
Beginning as early as the 12th century, some of the common fields in Britain were enclosed into individually owned fields, and the process rapidly accelerated in the 15th and 16th centuries. This led to farmers losing their land and their grazing rights, and left many unemployed. In the 16th and 17th centuries, the practice of enclosure was denounced by the Church, and legislation was drawn up against it; but the developments in agricultural mechanization during the 18th century required large, enclosed fields in order to be workable. This led to a series of government acts, culminating finally in the General Inclosure Act of 1801.
While farmers received compensation for their strips, it was minimal, and the loss of rights for the rural population led to an increased dependency on the Poor law. Surveying and legal costs weighed heavily on poor farmers, who sometimes even had to sell their share of the land to pay for its being split up. Only a few found work in the (increasingly mechanised) enclosed farms. Most were forced to relocate to the cities to try to find work in the emerging factories of the Industrial Revolution.
By the end of the 18th century the process of enclosure was complete.
Joseph Foljambe's Rotherham plough of 1730, while not the first iron plough, was the first iron plough to have any commercial success, combining an earlier Dutch design with a number of technological innovations. Its fittings and coulter were made of iron and the mouldboard and share were covered with an iron plate making it lighter to pull and more controllable than previous ploughs. It remained in use in Britain until the development of the tractor. It was followed by John Small of Doncaster and Berwickshire in 1763, whose 'Scots Plough' used an improved cast iron shape to turn the soil more effectively with less draft, wear, or strain on the ploughing team.
Andrew Meikle's threshing machine of 1786 was the final straw for many farm labourers, and led to the 1830 agricultural rebellion of Captain Swing (a probably mythical character comparable to the Luddite's Ned Ludd).
In the 1850s and '60s John Fowler, an agricultural engineer and inventor, produced a steam-driven engine that could plough farmland more quickly and more economically than horse-drawn ploughs. His ploughing engine could also be used to dig drainage channels, thereby bringing into cultivation previously unused swampy land. Although faster than horse-drawn ploughing, the capital costs of a pair of engines would often be too much for a single farmer to purchase for his own exclusive use, which lead to the development of an independent contracting industry for ploughing.
During the Middle Ages, the open field system had employed a three year crop rotation, with a different crop in each of the three fields, eg. wheat and barley in two, with the third fallow. 'Fallow' is a term which means that the field is empty, there is nothing growing there. Over the following two centuries, the regular planting of nitrogen-rich legumes in the fields which were previously fallow slowly increased the fertility of croplands. The planting of legumes (leguminosae, plants of the pea/bean family) helped to increase plant growth in the empty field because they used a different set of nutrients to grow than the grains. The legumes put back nutrients the grains used, nitrates produced from nitrogen in the atmosphere, and the grains put back the minerals the legumes used. In a way, they fed each other. Other crops that were occasionally grown were flax, and members of the mustard family. Medieval record keepers did not distinguish between rape seed or other mustards grown for animal feed and mustard grown for mustard seed for condiments. When the pastures were brought back into crop production after their long fallow, their fertility was much greater than they had been in medieval times. The farmers in Flanders (current day Belgium), however, discovered a still more effective four-field rotation system, introducing turnips and clover to replace the fallow year. Clover was both an ideal fodder crop, and it actually improved grain yields in the following year (clover is part of the pea family, leguminosae). The improved grain production simultaneously increased livestock production. Farmers could grow more livestock because there was more food, and manure was an excellent fertilizer, so they could have even more productive crops. Charles Townshend learned the four field system from Flanders and introduced it to Great Britain in 1730.
The increase in population led to more demand from the people for goods such as clothing. A new class of landless labourers, products of enclosure, provided the basis for cottage industry, a stepping stone to the Industrial Revolution. To supply continually growing demand, shrewd businessmen began to pioneer new technology to meet demand from the people. This led to the first industrial factories. People who once were farmers moved to large cities to get jobs in the factories. It should be noted that the British Agricultural Revolution not only made the population increase possible, but also increased the yield per agricultural worker, meaning that a larger percentage of the population could work in these new, post-Agricultural Revolution jobs.
The British Agricultural Revolution was the cause of drastic changes in the lives of British women. Before the Agricultural Revolution, women worked alongside their husbands in the fields and were an active part of farming. The increased efficiency of the new machinery, along with the fact that this new machinery was often heavier and difficult for a woman to wield, made this unnecessary and impractical, and women were relegated to other roles in society. To supplement the family's income, many went into cottage industries. Others became domestic servants or were forced into professions such as prostitution. The new, limited roles of women, dubbed by one historian as "this defamation of women workers", (Valenze) fueled prejudices of women only being fit to work in the home, and also effectively separated them from the new, mechanized areas of work, leading to a divide in the pay between men and women.
Towards the end of the 19th century, the substantial gains in British agricultural productivity were rapidly offset by competition from cheaper imports, made possible by advances in transportation, refrigeration, and many other technologies. From that point, farming in Britain entered a period of economic struggle which continues to the present day.
Prior to the Agricultural Revolution, perhaps half of land was kept in an open-field system, which included the village commons, where such activities as wheat threshing and animal grazing might take place. Parliamentary enclosures saw much of this being taken into private plots of land. With the elimination of the manor court, private property laws prevailed over what had once been land for common usage.