This experiment began in 1852 at Rothamsted, England. The site was
occupied (farmed?) since Roman times. Map of 1623 shows field in
arable. Arable crops 1847-1851. Clay-with-flints overlying chalk; ...
This experiment was established in 1958 and consists of a continuous
corn system with various levels of nitrogen application. In the
preceding 25 years, there was continuous corn
with residue burning. ...
This experiment began in 1843. The site was possibly farmed since
Roman times (i.e at least 1500 years). Map of 1623 shows field in
arable use. 1839-1843 arable crops: turnips, barley, peas, wheat, ...