The EBS has three levels of hierarchy to describe where experiments are carried out:

1. Sites

2. Fields

3. Planting Areas

All of these are “geospatial” objects. Ideally they should be defined by a “shape” that describes the full perimeter of the site, field, or planting area using latitude and longitude to describe each vertex. But, when this is not known, a single point describing the latitude and longitude can be used as an alternative.

Site

Sites are at the top level and would typically refer to a stable place such as a:

• Breeding station managed by a CG Center

• Experimental station managed by a NARS partner

• Agricultural university

• Seed company facility

• Farmer’s field

Field

Fields are one level below sites. At official facilities, these would also likely be stable over time, for example, a particular block at an experimental station. But in the case of a farmer’s field, the site and field may both represent the same geospatial area.

Planting Area

Planting areas are one level below Fields and describe the actual area that is planted with a uniform type of plot. In many cases, the Planting Area will cover the whole area of a field. But, if a field needs to be sub-divided, for example, into 2-row and 4-row plots, then two different planting areas would be created. Similarly, if part of a field were used to plant 2.5 m-long plots and the rest of the field were used to plant 5 m-long plot , two different planting areas could be created.

In general, a site can have one or more fields and a field can have one or more planting areas.