2016-04-22

Authors: Ignacio Ciampitti, Mary Knapp

Significant rains fell across the state during the week of April 15-21, with the heaviest amounts in the west. All divisions averaged above normal precipitation for the week, with the western divisions ranging from almost 5 times normal in the northwest to more than 8 times normal in the southwest. Percentages of normal tapered off in the east as the system was slow to move eastward. Eastern divisions ranged from just less than 2 times normal in the east central to almost 3 times normal in the northeast. In the areas with the heaviest rainfall, not only did precipitation range above average for the week, the totals erased both the monthly and the year-to-date deficits.

The temperatures were likewise a mixed pattern. Areas with the heaviest rains were cooler than normal, while areas where the rains were delayed and light were warmer than normal. Departures ranged from 8.9 degrees F warmer than normal in the east to -6.8 degrees F cooler than normal in the west. Statewide average departure was 1.2 degrees F warmer than normal. The warmest temperature reported for the week was 84 degrees F at Richfield 1NE, in southwest Kansas, on the 15th. The coldest temperature reported for the week was 31 degrees F at Brewster 1W, Thomas County, on the 19th.

The 8- to 14-day outlook suggests a switch to increased chances of cooler-than-average temperatures for the period. This doesn’t address whether the wide swings will continue or how extreme the temperatures might be. The precipitation outlook is slightly tilted toward wetter-than-normal conditions across the state for the 8- to 14-day period. The latest 7-day precipitation forecast shows moderate precipitation for much of the state, with parts of eastern Kansas getting more than 2 inches of rain for the period. The May outlook favors increased chances of wetter-than-normal conditions statewide. The temperature outlook is neutral, with equal chances of above- or below-normal temperatures.

Challenges for crop planting conditions and field operations

The weekly precipitation forecast for the Kansas is showing the probability of precipitation ranging from 0.1-inch in western Kansas to 2.0-inches in eastern Kansas. Additionally, the 8- to 14-day precipitation outlook is also showing a probability of better than 50% chance of above-average precipitation. The combination of the short-term forecasted precipitation and the 8- to 14-day outlook is a potential challenge for producers in planting corn and performing other field operations.

Planting corn under wet conditions can present several challenges. At this point, more than 50% of the corn acreage is still to be planted in the coming weeks. If possible, it is best to allow time for the soil to dry adequately before planting operations. Realistically for many farmers the potential number of days to get corn planted shrinks as we approach May. One of the main problems from planting into wet soils is the potential for soil compaction. Compaction problems can restrict adequate root growth, diminishing the ability of the plant to take up nutrients and water and affecting proper anchorage.

Under wet and cold conditions, corn emergence will be delayed, presenting several challenges on insect and disease pressure. The potential for uneven corn stands likely will be greater. This situation will directly affect plant-to-plant uniformity, which could have an impact on the potential yield.

Figure 1. Uneven corn stand due to cold, wet weather in late April. Photo by Ignacio Ciampitti, K-State Research and Extension.

Further details related to considerations for corn planted under wet conditions will be presented in future issues of the eUpdate.

Make sure to check our electronic resources:

Department of Agronomy: http://www.agronomy.ksu.edu

Extension Agronomy: http://www.agronomy.k-state.edu/extension/

Mesonet and other weather information: http://www.mesonet.ksu.edu

Ignacio Ciampitti, Crop Production and Cropping Systems Specialist
ciampitti@ksu.edu

Mary Knapp, Weather Data Library
mknapp@ksu.edu