Bean Binoculars Incident

Soybeans at the R5 (beginning seed) growth stage were scouted in early September. Symptoms of potassium deficiency were observed, including chlorosis of the top leaves. The pattern in the field follows previous field history of hay production, with the green streaks where the chaff wind row remained. This was observed across 75% of the field. Very little fertilizer has been applied to this field in recent years with hay production removing additional nutrients. 

Potassium deficiencies can be corrected during the flowering growth stages, but often times hidden hunger masks the problem until the seed fill stages when the deficiency is severe. Corrective applications should be made as quickly as possible, applying 60-120 lb K2O/ac with a granular fertilizer source based on Virginia recommendations. Foliar fertilizers are not recommended to correct a potassium deficiency.