Prolonged drought continues across Kansas. The state only received a little over half of the statewide average precipitation for September. Only isolated areas of north central, southwest, and southeast Kansas saw at or above-normal moisture, enough to improve soil moisture conditions temporarily (Figure 1). Unfortunately, even these areas have seen benefits rapidly diminished due to warm and breezy conditions. Over the last week, soil moisture has continued to dry out with negative changes at the 4-inch (10-cm) depth (Figure 2). Areas with little soil moisture change over the last week are likely already completely dried out.
Figure 1. Departure from normal precipitation over the last thirty days, from September 21 to October 18, 2023. Map by the Kansas Mesonet.
Figure 2. Change in volumetric water content at the 4-inch soil depth (10 cm) over the last seven days, as of October 18, 2023. Map by the Kansas Mesonet.
Weather forecast
Kansas's next 7-day precipitation forecast indicates that the region could see widespread moisture (Figure 3). Totals are only expected to range from 1-2 inches for much of the state, with locally higher amounts to 3 inches possible in south central Kansas. This would be well above average for the time of year, which ranges from 0.3 inches in the west to 0.8 inches in the southeast. The 6- to 10-day forecast favors an increased probability of above-normal precipitation continuing statewide (Figure 4). Beyond this period, conditions should dry back out for most of the state into early November.
Figure 3. Weekly precipitation forecast as of October 19, 2023, by the National Weather Service Weather Prediction Center (NOAA). For the next seven days, forecasted precipitation amounts in Kansas range from 1-2 inches, with locally higher amounts possible.
Figure 4. The 8- to 14-day precipitation forecast as of October 19, 2023, by the Climate Prediction Center, NOAA.
Wait for rain or continue with planting progress?
According to the USDA-NASS crop progress report, the current wheat-planted acreage in Kansas was 70% as of October 15, 2023. This is just above the 5-year average of 68%.
The biggest question in growers’ minds is: Should I continue planting the crop, or should I wait for rain?
Each grower must consider his or her situation before making this decision, as the rainfall distribution shown in Figure 1 is interpolated across weather stations and might not represent the reality for a few fields that were far from a given weather station.
At this point in time (October 19), and based on current soil conditions and weather forecasts, the advice would be to continue with crop planting now since we are at or past the optimum planting date for much of the state. Continuing crop planting now allows for taking advantage of the available moisture where recent rainfall occurred (that is, where moisture is still available, which is the case for some regions in north central Kansas) and also a good seed distribution in dryer soils where rainfall did not occur. In this situation, growers also have the opportunity to plant a large number of acres before it rains. If the short-term forecast of 1-3” precipitation materializes, this should allow for uniform crop emergence. However, suppose no rain occurs in the near future. In that case, the crop might not emerge until it rains later in the fall or even winter, delaying the “effective planting date” to whenever the rain occurs. Thus, at this point, growers should start to treat these fields as if they were sowing late, where increases in seeding rate and applications of in-furrow starter fertilizer are recommended. These might also be situations in which seed treatments can be beneficial, as the seeds will be exposed to weather in the fields for several days. See the accompanying article about management adjustments for late-planted wheat.
The worst-case scenario would include planting into a limited amount of moisture, just enough for the emergence of some plants but not enough to maintain these seedlings after they emerge. This situation can result in uneven stands and high stand variability within the field (Figure 5), or even crop failure. Thus, if good moisture cannot be reached in about the top 1.5 to 2 inches of soil, growers would likely be better off sowing it shallower and waiting for rain.
From a regional perspective, we are either around or slightly past the optimum planting window (south central and southeast Kansas) or already considerably past the optimum planting window (remainder of the state) for wheat. In these regions, if no moisture is available for immediate emergence and growers decide to plant the crop, they should start increasing seeding rates and adding more in-furrow phosphorus fertilizer to compensate for a late emergence.
For more information on planting wheat into dry soils, please see a previous eUpdate article from September 28, 2023: https://eupdate.agronomy.ksu.edu/article_new/considerations-when-planting-wheat-into-dry-soil-564-1.
Figure 5. Uneven wheat stands as a result of sowing into dry soils. Photo by Romulo Lollato, K-State Research and Extension.
Romulo Lollato, Wheat and Forages Specialist
lollato@ksu.edu
Christopher “Chip” Redmond, Kansas Mesonet Manager
christopherredmond@ksu.edu