The experiment's founder, John Bennet Lawes, was lord of the nearby Rothamsted Manor

Aerial view of the Park Grass Experiment

Aerial view of the Park Grass Experiment

Retrieving samples from the store in the 1930's

Sampling and storing crops and soils has continued without interruption for 150 years, creating a unique archive

Sorting weed seeds in the testimonial laboratory, 1890.

Harvesting Park Grass in the 1940's

Fertiliser treatments have obvious effects on the botanical composition of the plots

Dandelions only flourish where there is sufficient potassium and an alkaline soil

Some of the plots still show the wide diversity of broad-leaved and grass species that all hay meadows probably boasted at the time the experiment began

Some of the plots still show the wide diversity of broad-leaved and grass species that all hay meadows probably boasted at the time the experiment began

Snakes' head fritillaries flourish on one of the plots

An example of an analysis of results