The survey consisted of single visits of a half to one day in map squares of approximately 1,3 x 1 km until most of the country had been sampled.
During single visits of a half to one day all vascular plants were registered on a species list.
Older nomenclature has been converted into newer news (Heukels' flora 2005 nomenclature).
Observations were checked against the plant atlas (Atlas Nederlandse Flora) with a coarser grid. Observations that would lead to a new 5 x 5 km grid cells are temporarily omitted.
- * data entry is Turboveg with adapted species list and nomenclature
* conversion of gridsystem to coordinates (Arcview, Access)
* conversion of old plant names to recent ones, including 'sensu lato taxa' if lumped taxa were recorded at that time
* data validation against a coarser grid map in Access
* conversion to MySQL database for publication in IPT