Monthly Archives: September 2012

Drought Dichotomy

We often say water is the lifeblood of agriculture.  In a drought year like this, that truly is the case!  A case study showing the impacts of irrigated agriculture to Nebraska this year can be found here.

Interesting is the dichotomy we’re experiencing in south central Nebraska where irrigated fields that were truly fully irrigated may have some of the best yields producers have experienced while in so many areas of the State-even neighbors a few miles away-are experiencing the worst year they have ever faced.

Dryland yields have been all over the board mostly depending on tillage type.  Irrigated yields that were truly fully irrigated have been outstanding.  Hybrid Maize predictions for our area had been good all year for fully irrigated corn and it looks like they are even better than the long-term average predictions!

Yet, as I drive around the countryside I can’t help but wonder at how many corn stalks are already being disked under.  At a time when we’ve had several fires in our own State of Nebraska…when we have farmers and ranchers suffering trying to find forage for their livestock.  We are so blessed to have irrigation here and that buffers our producers from weather extremes.  But let’s not forget about the others who are hurting right now!  I would ask our producers with irrigated fields to please consider leasing your stalks for grazing or baling them this year to help those in need of forage.

Research from UNL shows that cattle and cornstalks go well together.

Some producers worry about compaction but in a dry year like this, compaction is essentially a non-issue-at least this fall.  UNL research from 1996-2011 showed the effects of fall and spring-grazing on subsequent corn and soybean yields.  On average,  yield of the following soybean crop was increased by about 2 bu/ac with fall-winter grazing, and 1.3 bu/ac with spring grazing, compared with no grazing of corn stalks.  Yield of corn as the second crop after grazing was not significantly affected resulting in an average of 1-3 bu/ac yield increase depending on fall or spring grazing. Check out this study and all our resources to help with drought decisions.

An upcoming Webinar called Cornstalk Grazing-Understanding the Values to Cattle Producers and Corn Farmers scheduled for  Oct. 2 from 12:30 to 1:10 p.m. will provide additional information.  If you are unable to view it, it will be recorded with all our Beef Webinars.

So while irrigation has provided life and good yields to many producers’ crops in the area, let’s not forget about our neighbors who are less fortunate.  Please consider leasing your corn stalks or baling them to help others in need of forage for their livestock!  You can connect with other producers by checking out the Hay and Forage Hotline at 800-422-6692.  This hotline lists hay and forage including cornstalks that is available via sale or donation.

Additional Resource:  How much to charge for cornstalk grazing?

Harvest #Soybeans at 13%

In spite of green stems and even leaves on some plants, soybeans are surprisingly drier than what you may think.  I’ve been hearing reports of soybeans in the 7-10% moisture range already in spite of there also being some “lima beans” along with the low moisture beans at harvest.

Harvesting soybeans at 13% moisture is a combination of skill and maybe some luck.  Why is 13% so critical?  A standard bushel of soybeans weighs 60 lbs. and is 13% moisture.  Often beans are delivered to the buyer at lower moisture than 13%.  The difference between actual and desired moisture content will result in lost revenue to the grain producer.  Here’s how the loss works based on UNL Extension’s “10 Easy Ways to boost profits up to $20/acre”:

  • Since 13 percent of the weight is water, only 87 percent is dry matter. The dry matter in a standard bushel is 52.2 pounds and the remaining 7.8 pounds is water.
  • If this bushel of soybeans is kept in an open basket and some moisture is allowed to evaporate, the net weight of beans would decrease. If the dry matter weight remains unchanged at the standard 52.2 pounds, the wet basis weight for any moisture content can be calculated.
  • For example, a standard bushel at 13 percent moisture weighs 60 pounds. If the moisture content were reduced to 11 percent (89 percent dry matter), the wet basis weight per bushel of the soybeans would be 52.2 pounds of dry matter divided by .89=58.65 pounds. (1.35 pounds less than the standard 60 lb. weight of beans initially placed in the basket). For each 52.2 pounds of dry matter delivered at 11 percent moisture, you miss an opportunity to sell 1.35 pounds of water.
  • It is standard practice for buyers to assume 60 pounds of soybeans constitutes a bushel when soybeans are at or below 13 percent moisture. When the beans are below 13 percent, the difference in water content is made up for by an equal number of pounds (wet basis) of soybeans.
  • Assuming a 60 bushel per acre yield and selling price of $8.50 per bushel, the potential extra profit the producer could realize if the beans are harvested at 13 percent moisture instead of 11 percent is $11.48 per acre.

Rapid dry-down and difficulty harvesting green stems and pods are the most common reasons for harvesting at lower than standard moisture. The following practices can help producers maintain quality and expected moisture content.

  • Adjust harvest practices. When harvesting tough or green stems, make combine adjustments and operate at slower speeds.
  • Begin harvesting at 14 percent moisture. Try harvesting when some of the leaves are still dry on the plant; the beans may be drier than you think. Soybeans are fully mature and have stopped accumulating dry matter when 95 percent of the pods are at their mature tan color.
  • Plan planting dates and variety selection to spread out plant maturity and harvest.
  • Avoid harvest losses from shattering. Four to five beans on the ground per square foot can add up to one bushel per acre loss. Harvest at a slow pace and make adjustments to the combine to match conditions several times a day as conditions change.

Grubs in Lawns!

The past week walking along the sidewalk to my office in the courthouse, I noticed the lawn browning and just thought “it must be late summer patch or brown patch”.  One day the custodian came into my office saying, “You’ve got to see this!”.

So we went outside and sure enough, we could roll the turf back like a carpet and there were up to 10 grubs in a small patch the size of a dinner plate in several areas of the lawn!  We definitely had a grub problem but no fear as it can be resolved.

If you are seeing brown patches in your turf right now, see if you can roll the turf back like a carpet.  If it comes easily with no attached roots, it very well may be a grub problem.  See if you can view any grubs present; you may have to dig in the soil a little.

What you can do:

Grubs can be controlled this time of year with Trichlorfon (Dylox)  and carbaryl (Sevin).  Please read and follow label directions.  Watering the products in will increase efficacy and help grass roots begin to re-establish.  

If you had a large patch affected and you’re concerned about it coming back, you can always power-rake to remove the dead material and overseed to re-establish grass in that area.

For more information on different types of grubs, please see the following Blog post by my colleague Elizabeth Killinger.

Latest 2012 #Corn Yield Predictions

2012 Corn Yield Potential Forecast Based on Aug. 27 Hybrid-Maize Simulation:  Irrigated corn yield potential is predicted to be 2-8% below long-term average, while dryland yield potential in much of the Corn Belt will be moderately to severely reduced, falling 22-67% below normal. Predictions are assuming no stress during pollination and fully irrigated fields with no equipment, disease, or insect problems.
Map of sites used for yield forecasts

Figure 1. Locations used by the Hybrid-Maize model for in-season yield forecasting with actual weather and dominant management practices and soil series at each site (indicated by stars).  Green areas indicate where corn is planted.  Weather data used is from the High Plains Regional Climate Center and the Water and Atmospheric Resources Monitoring Program through the Illinois Climate Network (Illinois State Water Survey, Prairie Research Institute, and the University of Illinois at Urbana-Champaign). Link to a larger version of Figure 1. 

Simulations were run for dryland corn in Iowa, Illinois, and South Dakota, and for both irrigated and dryland corn in Nebraska. Simulations were based on the typical planting date, hybrid relative maturity, plant population, and soil properties at each location. Underpinning data used in these simulations are provided in Table 1. To evaluate the impact on potential production at 12 sites across the Corn Belt (Figure 1), we used the Hybrid-Maize model  to estimate end-of-season yield potential based on actual weather up to August 27, and historical long-term weather data to complete the season using data from each of the past 30 years. This approach gives a “real-time,” in-season estimate of expected yield potential (the median value shown in Table 1) depending on weather conditions from August 27 until the corn crop reaches maturity.

August 27 projections give a narrower range than our projections based on August 13 simulations, and, at some locations the crop reached blacklayer during the past week (Mead, Concord, O’Neill, and Nashua, Iowa). Projected yield potential since August 13 has not changed by more than 7% across all locations, except for the two locations in west central Illinois (Monmouth) and south central Illinois (Bondville) where predicted dryland yield has increased by 30% due to good rains and cooler weather. It should be noted, however, that if unusually hot, dry weather occurred during pollination at these Illinois locations, such a large yield improvement would not be expected due to reduced seed set. Still, projections of final yield potential are below the long-term average at all sites, under both irrigated and dryland conditions (Table 1).

The bottom line is that 2012 irrigated yields will be moderately lower than the long-term averages (2-8% below normal), while dryland corn yield potential in much of the Corn Belt will be moderately to severely reduced (22-67% below normal). It is important to keep in mind that yields can be even lower at places where both prolonged drought and high temperature stress at pollination have occurred. Also, greater field-scale variability is being observed this year in irrigated fields due to the inability of some irrigation systems to keep up with crop water use demand, problems with pivot irrigation nozzles and uneven watering, and additional stresses from insects and diseases. Such problems can contribute to reduced yields at irrigated sites of more than the 2-8% simulated by the model.There is a modest yield loss (5-8%) for locations in South Dakota (Brookings) and west central and north central Illinois (Monmouth and DeKalb) while a moderate yield loss of 22-28% is predicted for dryland corn in central and northeast Iowa (Gilbert and Nashua). Severe yield loss of 32-67% is projected for dryland corn in south central, eastern, and northeastern Nebraska (Clay Center, Mead, and Concord), northwest Iowa (Sutherland), and south central Illinois (Bondville) (Table 1). In contrast to large loss of yield potential in these dryland systems, the projected losses in yield potential at all irrigated sites are modest at about 2-3% in south central Nebraska (Clay Center, Holdrege), and 7-8% in east and northeast Nebraska (O’Neill, Concord, and Mead) (Table 1). Projected irrigated yield potential since August 13 has increased by about 3% due to cooler weather during the past two weeks.

Patricio Grassini, Research Associate Professor, Agronomy and Horticulture Department
Jenny Rees, UNL Extension Educator
Haishun Yang, Associate Professor, Agronomy and Horticulture Department
Kenneth G Cassman, Professor, Agronomy and Horticulture Department

Earlier Hybrid-Maize Predictions

Table 1.  2012 In-season yield potential forecasts as of August 17  using UNL Hybrid-Maize Model

Location, State Water Regime Soil Type&
Initial Water
Planting Date Long-term
2012 Forecasted Yp (bu/ac)

Holdrege, NE Irrigated Silt loam 32.4k 113  April 27  248
Clay Center, NE Irrigated


Silt clay loam

100% ASW



113 April 23

April 23

Mead, NE Irrigated


Silt clay loam

100% ASW



113  April 30  240
Concord, NE Irrigated


Silt loam

100% ASW



104 May 3 235
O’Neill, NE Irrigated Sandy loam

100% ASW

32.4k 106  May 3 225

Brookings, SD Rainfed Silt clay loam

100% ASW

30.0k 98  May 4 120

Sutherland, IA Rainfed Silt clay loam

100% ASW

31.4k 99  May 1 168
Gilbert, IA Rainfed Loam

100% ASW

32.4k  110  April 26 200
Nashua, IA Rainfed Loam

100% ASW

32.4k 99  May 1 198

Monmouth, IL Rainfed Silt loam

100% ASW

32.4k 112  April 27 212
DeKalb, IL Rainfed Silt clay loam

100% ASW

32.4k 111  May 1 201
Bondville, IL Rainfed Silt clay loam

100% ASW

32.4k 114  April 20 197

  Simulations based on dominant soil series, average planting date, and plant population (PP) & relative maturity (RM) of most widespread hybrid at each location (Grassini et al., 2009). 

 Average (20+ years) simulated yield potential (Yp). 

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