As Iowans know,  April weather delayed the start of the growing season greatly in the north-central United States and much of the Midwest, as well as spring fieldwork and early corn planting. Nearing the end of April, some corn had been planted mainly in the central and southern Midwest, but progress was behind the five-year average pace.  Conditions for fieldwork were improving in late April in many areas, however.

Weak to occasionally moderate La Nina conditions that began...