2017-10-09

Authors: Romulo Lollato, Mary Knapp, Andres Patrignani

Precipitation in the Kansas wheat growing region during the period of October 2 – 8 brought anywhere from <0.6 of an inch in the far western tier of counties to as much as 6.8 inches in portions of northwest, central, and north-central Kansas (Figure 1). This early-October precipitation occurred after above-normal precipitation in late-September, resulting in fields with a full soil moisture profile for most of the state (Figure 2), but also in water-logged soils which are delaying field work (Figure 3).

Figure 1. Cumulative precipitation during October 2 – 8, 2017. Map by K-State Weather Data Library.
Figure 2. Calculated soil moisture anomaly across the United States as of October 8, 2017. Central and western Kansas shows anywhere from 1.6 to 3.2 inches of positive anomaly. Map by Climate Prediction Center (http://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Soilmst/Soilmst.shtml#)
Figure 3. Water-logged fields in northwest Kansas as of early October 2017. Photo courtesy of Justin Gilpin, Kansas Wheat Commission.

These suboptimal conditions for field work caused by the excessive rains resulted in a delay in sowing progress in Kansas. Historically, according to crop reports by the USDA-NASS, 35% of Kansas wheat is usually sown by October 5, and 41% by October 11. This year, the crop stands at only 14% sown (Figure 4).

Figure 4. Wheat sowing progress in Kansas during 2017 (dashed line) compared to the 1994 – 2016 average (solid line) and range (purple area). Wheat area sown in the current year is 21% behind the long-term average, and is the lowest percent observed since 1994, considerably below the range observed in the period. Graph based on USDA-NASS crop report of progress as of October 2, 2017.

In addition to already delayed sowing, most of Kansas fields are too wet to allow for any field work, which will likely cause a further delay in sowing progress and could cause some fields to be planted after the optimum sowing window for the region. If producers are forced to delay sowing past their optimal window, fall growing dynamics will change with less time to tiller. This sowing delay might require some management adjustments to maximize crop productivity.

Management adjustments to consider as sowing is delayed past the optimum sowing window include:

On a final note, a couple positive points about the sowing progress delay are:

Romulo Lollato, Extension wheat and forage specialist
lollato@ksu.edu

Mary Knapp, Weather Data Library
mknapp@ksu.edu

Andres Patrignani, Soil Water Processes specialist
andrespatrignani@ksu.edu