As of May 25 the Drought Monitor report continues to indicate improvement for soil moisture conditions for the western portion of the state with no real change in our area. None of the rains from Tuesday are reflected in the report. With the predicted rains today and into Monday, Kansas will stay out of drier soil conditions. The six to ten-day outlook (June 2 to 6) indicates below normal temperatures and slightly above normal precipitation south of Barton County below normal to our northwest. The eight to 14 day outlook (June 4 to June 10) indicates continued below normal temperatures and normal precipitation. This is good news for the wheat crop as it will allow it to mature at a normal rate and not terminate development early. After the anticipated rains today and tomorrow, this should also provide a chance for farmers to get back into the fields. Parts of the state this past week experienced torrential rains and flooding conditions. While the area immediately around Great Bend didn’t, flooded fields are close by. What effect will standing water have on crops in the field?
• First, what factors play a role in how damaging standing water is for crops? How long is the field flooded? Naturally the longer the time the more damaging. How warm is it? Crops can better cope with standing water under cooler conditions. Hot weather stresses the crop more quickly. How deep is the standing water relative to the height of the crop? Having the crop totally under water is naturally worse than if most of the crop is above water. Is the water standing or moving? Rapidly moving water can cause lodging.
• Second, how do flooded conditions effect crops? The root system supplies the whole plant with water and essential nutrients. Root cells, like any other living cells need oxygen to respire so if oxygen is limited, root cells have trouble maintaining themselves and growing, producing new root mass. Roots must constantly grow and explore the soils as that is where most water and nutrient uptake comes from. Just like us, crops aren’t efficient at extracting oxygen from water. If the saturated conditions last long enough, roots die and the crop dies. Even if the crop doesn’t die, the effects of standing water can result in nutrient deficiencies, stunted growth and a lack of turgor (plants wilting). The effects also have to do with the stage of growth. Just germinated or emerged plants are more severely affected more rapidly. The more mature the plant, the better able it is to survive. Even if the plant does survive, several days of standing water is likely to negatively impact yield. Also important is that these saturated conditions can lead to diseases such as root rot, seedling blight, and damping off.
• Third, the type of plant affects the plants ability to handle flooding conditions. Grass crops such as corn, wheat, and sorghum develop a fibrous shallow root system. This root system, concentrated near the soil surface is better situated to survive as it is closer to the surface and be able to obtain oxygen. Broadleaf crops such as soybean, canola, cotton, and alfalfa possess tap root systems. And the root system is much less fibrous. Flooded soils therefore cause serious damage and even plat death more quickly. The saying is that broadleaf crops don’t like wet feet and that’s why.
As always there are more possible effects such as increased weed pressure, loss of nutrients such as nitrogen, and newly planted seeds in standing water for several days will likely see decreased stands.
Dr. Victor L. Martin is the agriculture instructor/coordinator for Barton Community College. He can be reached at 620-792-9207, ext. 207.
