Just when you thought we were off and running for the planting season, Mother Nature has literally drowned those thoughts.

With totals now well past four inches for many of us and maybe even close to 5 just since Thursday, April 27, many fields are beyond saturation. The heavy rainfall last weekend that created lots of flooding and ponding of newly planted fields has had no relief with continued moisture.

Add to that the colder than normal May temperatures have created a recipe for replant more than likely for several recently planted acres.

A timely article by Ohio State Agronomy specialist Peter Thomison suggests that the extent to which ponding injures corn is determined by several factors, including: Plant stage of development when ponding occurs; duration of ponding; and air/soil temperatures.

Prior to the 6-leaf collar stage (as measured by visible leaf collars) or when the growing point is at or below the soil surface, corn can usually survive only 2 to 4 days of flooded conditions.

He notes that since most of the corn that’s been planted so far is not beyond the VE stage, it’s especially vulnerable to damage from ponding and saturated soil conditions.

The oxygen supply in the soil is depleted after about 48 hours in a flooded soil. Without oxygen, the plant cannot perform critical life sustaining functions; e.g. nutrient and water uptake is impaired, root growth is inhibited, etc. If temperatures are warm during ponding (greater than 77 degrees F) plants may not survive 24-hours.

Cooler temperatures prolong survival so the cooler than normal forecast this week may limit injury resulting from saturated soil conditions. Once the growing point is above the water level the likelihood for survival improves greatly.

Even if ponding doesn’t kill plants outright, it may have a long-term negative impact on crop performance. Excess moisture during the early vegetative stages retards corn root development.

As a result, plants may be subject to greater injury during a dry summer because root systems are not sufficiently developed to access available subsoil water. Ponding can also result in losses of nitrogen through denitrification and leaching.

Even if water drains quickly, there is the possibility of surface crusts forming as the soil dries that can impact the emergence of recently planted crops. Growers should be prepared to rotary hoe to break up the crust to promote emergence.

Thomison suggests for corn that’s emerged to check the color of the growing point to assess plant survival after ponding. It should be white to cream colored, while a darkening and/or softening usually precedes plant death.

For corn not yet emerged, evaluate the appearance and integrity of seeds or seedlings that have yet to emerge (likely rotting if discolored and softening). Look for new leaf growth 3 to 5 days after water drains from the field.

Disease problems that become greater risks due to ponding and cool temperatures include pythium, corn smut, and crazy top. Fungicide seed treatments will help reduce stand loss, but the duration of protection is limited to about 10-14 days.

The fungus that causes crazy top depends on saturated soil conditions to infect corn seedlings. There is limited hybrid resistance to these diseases and predicting damage from corn smut and crazy top is difficult until later in the growing season.

However, the economic impact of these latter two diseases is usually negligible.

Only time will tell us the extent of the damage, so once you can walk across your fields take the time to do so and evaluate the damage from excessive water.

While out evaluating fields don’t forget to evaluate your wheat if you have any acres.

First off, many fields are already headed, so fungicide treatments are going to be need much earlier. In fact it looks like we are as much as three weeks early with wheat.

Adult cereal leaf beetles have also been spotted in a few areas across Ohio. Adults do not normally cause yield loss in wheat, but, if present in high numbers, they could lead to heavy larval infestations over the next few weeks. Adult cereal leaf beetles are shiny, metallic blue and orange and are best found using a sweep net or by walking the field.

Cereal leaf beetle larvae are small, gray and moist, resembling bird droppings, and are easily found on wheat leaves. Foliar damage on wheat occurs when larvae feed and strip the leaves, causing a “frosted appearance.”

Economic threshold of cereal leaf beetle larvae averages 1 per stem.

As wheat matures, growers should carefully inspect their fields for the presence of cereal leaf beetle larvae.

Tony Nye is the state coordinator for the Ohio State University Extension Small Farm Program and has been an OSU Extension Educator for agriculture and natural resources for 29 years, currently serving Clinton County and the Miami Valley EERA.