Hi Sunshine, "In the field" refers to anywhere where the work is being done. It means to be away from the center, engaged in practical work in the natural environment. Police in the neighborhoods are working in the field. Teachers in classrooms are working in the field. Nurses in hospitals are working in the field. I hope this helps, Stephen

The place where outdoor research takes place is usually referred to as 'the field'. In this instance the researchers were working outdoors collecting data on seeds.