Corn and dry soils at planting, looking ahead

decrease font size  Resize text   increase font size       Printer-friendly version of this article Printer-friendly version of this article

Dry conditions persist in many parts of Iowa. As of Jan. 30, modeled volumetric root-zone soil water in the northwestern half of the state was one-third or less (see Mesonet map). Elwynn Taylor, Iowa State University Extension and Outreach climatologist, indicates there is some probability that these dry conditions will persist.

What if it is dry at planting in 2012?

Methods
We don’t have specific research experiments planted every year in Iowa to provide actual yield data for dry planting conditions – we don’t often have dry soils at planting. However, modeling tools that simulate dry conditions at planting help us understand the effect of dry conditions on potential yield. The corn simulation model Hybrid-Maize can address several questions regarding corn management practices. The model uses historic weather data from automated weather stations. I used data from five of ISU’s Research and Demonstration Farms, one in each of the four corners of Iowa and the other near Ames in central Iowa.

click image to zoom The model allows users to change soil moisture conditions at planting to simulate different possibilities. With this capability, we can address the question, “What if the soils are only half field capacity (FC) at planting?”

In this exercise I compared two moisture levels: A. 75 percent field capacity (FC) in the topsoil (0-12 inches) and 100 percent FC in the subsoil (12-40 inches), and B. 50 percent FC in both topsoil and subsoil. I realize that many soils now are drier than 50 percent FC so the second possibility may be overly optimistic for those areas. Other common inputs for each site modeled are provided in Table 1. Factors that varied across locations such as soil textures are shown in Table 2.

click image to zoom Simulation Results
Without changing hybrids or plant populations, with drier soils at planting, probabilities of reduced yield vary depending on the location in the state (Table 3). If we have a year with weather conditions like those of 2011 at the five locations with the stipulation of planting into dry soils, yield potentials at the Northwest (NW) Sutherland, Northeast (NE) Nashua, and Central Ames research farms would be similar to what they would be if the soils were moist at planting. The weather experienced at each of these sites was sufficient to overcome any disadvantage of the dry soil planting conditions. However, at the Southwest (SW) Lewis farm yields would be 64 percent of those of a wet soil at planting; at the Southeast (SE) Crawfordsville farm, 70 percent.

click image to zoom Another way to think about yield potentials is to look at probabilities of experiencing a year that would provide yield reductions with dry soils at planting. A median year at NW, SW and SE would result in sizeable yield reductions if soils were dry at planting. A 25 percentile year would reduce yields at NE if soils were dry at planting, and only the worst year since 1986 would reduce yields at the Central location.

We all know that many things can happen between now and planting. If soil moisture conditions do not improve by planting, yields will be reduced at many Iowa locations. Meanwhile, let’s hope for complete recharge of our soil before planting and a good year!

Endnote: This article and the two associated with it summarize portions of the 2012 Crop Advantage Series (CAS) talk entitled “Long silks, short pollen,... long year” presented in January 2012. Slides from that presentation with more detail are available here: CAS Presentation Slides.


Buyers Guide

Doyle Equipment Manufacturing Co.
Doyle Equipment Manufacturing prides themselves as being “The King of the Rotary’s” with their Direct Drive Rotary Blend Systems. With numerous setup possibilities and sizes, ranging from a  more...
A.J. Sackett Sons & Company
Sackett Blend Towers feature the H.I.M, High Intensity Mixer, the next generation of blending and coating technology which supports Precision Fertilizer Blending®. Its unique design allows  more...
R&R Manufacturing Inc.
The R&R Minuteman Blend System is the original proven performer. Fast, precise blending with a compact foot print. Significantly lower horsepower requirement. Low inload height with large  more...
Junge Control Inc.
Junge Control Inc. creates state-of-the-art product blending and measuring solutions that allow you to totally maximize operating efficiency with amazing accuracy and repeatability, superior  more...
Yargus Manufacturing
The flagship blending system for the Layco product line is the fully automated Layco DW System™. The advanced technology of the Layco DW (Declining Weight) system results in a blending  more...
Yargus Manufacturing
The LAYCOTE™ Automated Coating System provides a new level of coating accuracy for a stand-alone coating system or for coating (impregnating) in an automated blending system. The unique  more...
John Deere
The DN345 Drawn Dry Spreader can carry more than 12 tons of fertilizer and 17.5 tons of lime. Designed to operate at field speeds up to 20 MPH with full loads and the G4 spreader uniformly  more...
Force Unlimited
The Pro-Force is a multi-purpose spreader with a wider apron and steeper sides. Our Pro-Force has the most aggressive 30” spinner on the market, and is capable of spreading higher rates of  more...
BBI Spreaders
MagnaSpread 2 & MagnaSpread 3 — With BBI’s patented multi-bin technology, these spreaders operate multiple hoppers guided by independent, variable-rate technology. These models are built on  more...


Comments (0) Leave a comment 

Name
e-Mail (required)
Location

Comment:

characters left


Pacesetter Grain Hopper

The Pacesetter Gain Hopper features original and innovative ideas like the patented RollerTrap™, the industry’s easiest to open and maintain trap ... Read More

View all Products in this segment

View All Buyers Guides

Feedback Form
Feedback Form