Step function from Fert_Office v1.26 foglio Gri_K (righe 23-28): clay < 5.1% -> 60 kg K2O/ha; 5.1-15.1 -> 30; 15.1-25.1 -> 20; >= 25.1 -> 10.
Step function from Fert_Office v1.26 foglio Gri_K (righe 23-28): clay < 5.1% -> 60 kg K2O/ha; 5.1-15.1 -> 30; 15.1-25.1 -> 20; >= 25.1 -> 10.