The fields were most likely cultivated all year round. They were filled with colourful species of weeds, such as cornflower and corn cockle, which have disappeared from the fields today.
Corn cockle seeds are poisonous and have to be removed before corn is ground into flour. If the seeds become incorporated into bread then the crumbs are a blue-green colour, the taste is sharp and eating the bread brings on drowsiness. The seeds are poisonous to hens and pigs. However, they are edible if roasted.