The Dutch soil physical units map, called BOFEK, was created to show how soil properties can be upscaled from individual samples to a national scale. By grouping soil samples based on texture, researchers derived average water retention and hydraulic conductivity characteristics for different soil types. These characteristics were used to cluster soil profiles into 79 units, forming the soil physical units map for the Netherlands. The study found that simulated transpiration reduction using these units closely matched results from individual soil profiles, with less than a 5% difference in most cases. This map can help in understanding water balance terms like transpiration, evaporation, and surface runoff at a national scale.