Farmers may be wondering ‘what’s next?’ following another round of challenging weather.
This weekend, hail pelted crops in central Nebraska and last night, excessive rain flooded fields in eastern Nebraska.
In this feature interview, Nebraska Extension Educator Jenny Rees shares the latest insights on potential crop damage and what farmers can do next.
She’s also shares experience from last year and how producers can use that information to make decisions this season.
The following information is courtesy of UNL’s Cropwatch website:
Crop Survival
Corn and soybean progress varied across the impacted area, depending on the planting date. Flood damage depends on several factors:
- crop growth stage and development,
- frequency and duration of flooding,
- air-soil temperature, and
- field drainage capabilities.
If temperatures are warm and soils are saturated with water, plant respiration rates will increase. This causes oxygen levels to decline rapidly in the soil and more plant stress to occur. Two CropWatch articles written by Timmerman et al. (2018) describe how long corn and soybeans can be under water before plant death occurs. A brief summary follows:
Corn
- Prior to V6: Plants can survive under water for 2-4 days if temperatures do not exceed 77°F.
- V7—V10: Plants can survive 7-10 days if temperatures do not exceed 86°F.
- VT—R1: Reduced nutrient uptake and successful pollination if standing water is present longer than 2-4 days. Yield losses may occur.
Soybeans
- Yield losses minimal if flooding lasts less than 48 hours.
- Flooded for 4-5 days, fewer nodes develop and plants will be shorter.
- Flooded for 6+ days, possible stand and yield loss. The longer it takes a field to dry out, the more yield loss that may occur.
- Soybeans at flowering: Potential yield loss, especially on poorly drained soils.
- R3—R5: Higher yield loss potential
Bob Nielson, Purdue University extension agronomist, recently wrote an article on the “Effects of Flooding or Ponding on Corn Prior to Tasseling” and noted some additional things to keep in mind:
- Completely submerged plants are at higher risk than partially submerged plants.
- Soil oxygen is depleted within 48 hours of soil saturation, causing root stress.
- Mud or soil on the plants reduces photosynthesis and may pre-dispose plants to diseases.
- New root growth may be stunted after flooding.
- Plants may turn orange or purple due to nutrient deficiencies or deteriorating roots.
- Diseases such as common smut, crazy top, or root and stalk rots may develop. (See related story.)
- Plants may be more susceptible to green snap or root lodging.
Unfortunately, it’s a waiting game to see how the crop looks once floodwaters recede. Be sure to take diligent records and photos and talk to your crop insurance adjuster to determine if crop loss occurred.
