The best laid intentions are sometimes met with a field-soaking thunderstorm. How does corn cope with standing water or saturated soils? Researchers at Kansas State University recently tackled this topic in a recent issue of their Extension agronomy eUpdate.
The good news? “Corn plants can recover with minimal impact on yield if the plants stay alive and conditions return to normal quickly,” the researchers note.
The clock is ticking on waterlogged fields, however. Corn can survive between two and four days of flooding prior to the V6 growth stage.
“Chances of survival increase dramatically if the growing point was not completely submerged, or if it was submerged for less than 48 hours,” according to the K-State researchers. “After 48 hours of soil saturation, soil oxygen is depleted and critical plant functions [such as] photosynthesis, water and nutrient uptake are impaired.
After V6, the growing point is usually above the surface of flooded fields, leaving plants less susceptible. Research pins a 5% to 32% yield reduction on early season flooding, depending on the duration of flooding and how much nitrogen is leached from the soil.
However, some longer-term problems could persist throughout the season if the corn crop has to fight standing water or saturated soils early in the season. For example, they tend to be more prone to late-season root rot and stalk rots later in the summer. Saturated soils can also lead to shallower root systems, which lead to standability concerns later in the season during periods of high winds.
Some of these problems can be partially mitigated by hybrid selection, but no hybrid is completely immune to these issues, the K-State researchers report.
“The best advice is to scout your corn after water drains form the fields,” they conclude. “Check the appearance of new leaves and the standability of the corn.”
Click here for additional advice on dealing with standing water or saturated soils.