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Wordless Wednesday: Technology in Ag
Captured pics of slides at last week’s Nebraska Ag Technology Association Conference. What comments do you have about them?
On-farm Research
Wow, I’m sorry I haven’t published much the past two months! Much has happened though as we’re in the middle of winter Extension ag programming season! I love this time of year seeing farmers and ag industry reps-and just chatting about what happened last year and speculating about the upcoming season.
Many of you are also attending numerous meetings. You’re gathering information regarding products and production practices. You may be wondering “Will this work on my farm?” Why not go a step further and see for yourself? On-farm research is a great way to test these questions for yourself using your own equipment in your own fields!
UNL Extension has partnered with the Nebraska Corn Board and Nebraska Corn Growers to form the Nebraska On-farm Research Network. There are three main studies we are conducting state-wide: corn population, corn nutrient, and corn irrigation studies…but we are open to helping you design a valid research experiment for your field to test what you would like-and it can be for a crop other than corn.
We have some upcoming opportunities for you to learn more. On February 11 and February 12 from 9:00 a.m.-3:00 p.m. at UNL’s Ag Research and Development Center near Mead and the York Co. Fairgrounds in York respectively, growers who conducted on-farm research in 2012 will be sharing their results; you can also learn more about conducting on-farm research in your own field. There is no charge for the meetings courtesy of the Farm Credit Services of America but we do need an RSVP for meal count and handouts. Please RSVP by calling (402)624-8030 for ARDC or (402)362-5508 for the program in York. I hope to see you at these meetings as well!
Research Fertilizer Options for Your Farm
November 1 is just around the corner-the beginning of when fall fertilizing occurs in this area of the State. Hopefully many of you have taken soil samples as excess nitrate is to be expected after this drought year. This is an excellent time to consider evaluating your nitrogen program by starting an on-farm research trial!
On-farm research is using your own equipment, in your own fields, over single or multiple growing seasons allowing you to determine the most economical, efficient, and sustainable practice for the production of irrigated and/or dryland crops on your own farm.
What are the soil fertility questions you have for your farm?
Right now, with fertilizing on producers’ minds, we’re hoping you will consider a soil fertility study. We have several example nutrient protocols
including the UNL N fertility rate compared to +/- 30 lbs, and considerations for nitrogen timing studies such as pre-plant, sidedress, or fertigation. You can view all these plot designs by clicking on 2012 protocols. If you are planning on applying anhydrous this fall, be sure that the anhydrous strips are the correct width, as the corn must be harvested and weight determined in a correct manner next fall.
When designing a nitrogen comparison you need to remember nitrogen is a mobile nutrient and corn roots will spread laterally. Therefore, the width of the treatments must take this into account and compensate for it. If you have a 16 row nitrogen applicator and an 8 row corn head, you will need 32 rows of each nitrogen rate. Each 32 row strip must be repeated 4 times. At harvest, in each 32 row block, you must record and weigh the center 16 rows with two separate weights i.e. 8+8 . This is done for statistical analysis purposes. Without statistics, you cannot determine if differences between treatments is the result of the nitrogen rate or because of soil variability.
What’s in It for You?
On-farm research in your own fields allows you to find answers to the questions you may have. We all read articles or hear presentations about various practices and products. The question is “Will it work on my farm?“. That’s what on-farm research allows you to find out!
UNL Extension Educators and Specialists are here to help you design your on-farm research trials, help you with data collection, and will statistically analyze the data for you at the end of the season. Correct plot setup is critical to reduce any error in favoring one treatment over another (because we know fields are variable and some portions of the field will yield better than others). The statistical analysis is another tool which helps us determine how much any yield differences between treatments are due to the treatments themselves or to chance.
So if you have an idea you’d like to try, please contact any of the UNL Extension Educators or Specialists working with on-farm research! The Nebraska On-farm Research Effort is a partnership between the Nebraska Corn Board, Nebraska Corn Growers Association, and UNL Extension.
On-farm research may sound daunting, but today’s equipment makes it easier than ever. It does take a little extra time, but our farmers conducting on-farm research feel the value of knowing the results of a study on their own piece of ground make the effort worthwhile.
What are some on-farm research studies you would like to conduct this year or that you would like our group to consider?
Fall Fertilizing Considerations
With the early harvest and potential product discounts, producers may be considering fall fertilization soon. I can appreciate the reasons for it such as the product discounts, covering acres, and the fact that we don’t know what spring weather will bring in order to fertilize before planting.
At the same time applying nitrogen when a growing crop is not present allows for nutrient loss and we continue to see nitrates in groundwater increase in some areas. Check out the following Webcasts regarding research from UNL Soil Fertility Specialists as you consider nutrient application and the addition of nitrogen inhibitors.
Guidelines for Fall Fertilizing
If you do apply fertilizer in the fall, the Natural Resources District (NRD’s) have provided guidelines so please check specifically with them. Both UBBNRD and LBNRD have said no fall fertilization before November 1st and recommend no fall fertilization when soil temperatures are above 50°F. This is because the conversion of anhydrous ammonia is much slower once soil temperatures are consistently below 50°F. Please see the CropWatch Soil Temperature page for a map of current soil temperatures.
LBNRD also recommends but doesn’t require a nitrogen inhibitor placed with the anhydrous in the fall. No liquid or dry nitrogen fertilizer can be applied between November 1st and March 1st without receiving a fertilizer permit. With the fertilizer permit, producers will be required to put a nitrogen inhibitor in with their dry or liquid fertilizer.
Two exemptions are provided in the spreading of manure, sewage, and other by-products conducted in compliance with state laws and regulations, and the applications of pre-plant starter nitrogen to fall seeded crops, such as wheat.
A few other considerations from UNL Soil Fertility Specialists:
- Take soil samples as soil nitrates may be higher than normal this fall-particularly in dryland fields.
- Dry soils are difficult to sample and may affect results. Soil organic matter and soil nitrate results should be fine, but some soil pH and potassium may be affected by the dry conditions.
- Knife applications, including sealing of anhydrous ammonia injection tracks, also may be more difficult in dry soil conditions.
- Monitor rain and snow infiltration between now and the next growing season and make fertilizer adjustments next spring if excessive rain may have caused leaching.
Additional Resources
On Farm Research
As harvest rolls to a close you most likely noticed some field variability or have some questions about how various products or production practices may work on your farm. Every year during the winter, UNL Extension educators share research conducted by your peers-other farmers-in their own fields and often those presentations are very interesting to our clientele.
With the advance of farming technologies, it’s easier than ever for more farmers to conduct research on their own farms. Depending on the study, there may be additional time involved, but overall, the farmers I’ve worked with who have conducted on-farm research say they obtained answers to their questions and the power was knowing it was research based on their own farm.
Last winter the two on-farm research groups in Nebraska combined to form the Nebraska On-Farm Research Network. With help from the Nebraska Corn Growers and Nebraska Corn Board, three State-wide studies were rolled out in addition to other studies that producers wanted to conduct on their own farms. That data is still being collected and analyzed right now and results will be presented this winter.
So as you think about the 2012 season, what are the questions you have? Consider working with your local Extension Educator to design a valid research-based experiment to answer the questions on your farm. To learn more, please check out the CropWatch on-farm research page.
What studies would you like to see our group research on-farm in 2013?
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.
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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 | |||||||||
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| Location, State | Water Regime | Soil Type¶& Initial Water |
Plant Pop.¶ (ac-1) |
Relative Maturity (days) |
Planting Date¶ | Long-term Yp (bu/ac)‡ |
2012 Forecasted Yp (bu/ac) | ||
| Median | |||||||||
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| Holdrege, NE | Irrigated | Silt loam | 32.4k | 113 | April 27 | 248 |
243 | ||
| Clay Center, NE | Irrigated
Rainfed |
Silt clay loam
100% ASW |
32.4k
24.0k |
113 | April 23
April 23 |
250 146 |
242 98 |
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| Mead, NE | Irrigated
Rainfed |
Silt clay loam
100% ASW |
32.4k
28.0k |
113 | April 30 | 240 160 |
224 53 |
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| Concord, NE | Irrigated
Rainfed |
Silt loam
100% ASW |
32.4k
29.0k |
104 | May 3 | 235 154 |
218 90 |
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| O’Neill, NE | Irrigated | Sandy loam
100% ASW |
32.4k | 106 | May 3 | 225 |
207 | ||
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| Brookings, SD | Rainfed | Silt clay loam
100% ASW |
30.0k | 98 | May 4 | 120 |
110 | ||
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| Sutherland, IA | Rainfed | Silt clay loam
100% ASW |
31.4k | 99 | May 1 | 168 |
104 | ||
| Gilbert, IA | Rainfed | Loam
100% ASW |
32.4k | 110 | April 26 | 200 |
145 |
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| Nashua, IA | Rainfed | Loam
100% ASW |
32.4k | 99 | May 1 | 198 |
155 | ||
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| Monmouth, IL | Rainfed | Silt loam
100% ASW |
32.4k | 112 | April 27 | 212 |
189 | ||
| DeKalb, IL | Rainfed | Silt clay loam
100% ASW |
32.4k | 111 | May 1 | 201 |
190 | ||
| Bondville, IL | Rainfed | Silt clay loam
100% ASW |
32.4k | 114 | April 20 | 197 |
134 | ||
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| ¶ 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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Aflatoxin Concerns in #Corn
This article originally appeared in http://cropwatch.unl.edu written by Dr. Tamra Jackson-Ziems, UNL Extension Plant Pathologist.
Drought and high temperatures promote development of the disease Aspergillus ear rot (pictured right). The fungi that cause this disease (most commonly, Aspergillus flavus) can produce aflatoxin. Aflatoxin is one of many chemicals in a group known as mycotoxins that are produced by fungi (molds). Mycotoxins, such as aflatoxin, can be toxic to animal and human consumers and, at certain concentrations, can lead to dockage or rejection of grain at elevators.The unusually high temperatures and drought this summer are having severe impacts on Nebraska corn. In addition to reductions in test weight and overall yield, secondary problems are developing in some corn fields as a result of these conditions.
Corn harvested for grain to this point has been predominantly from fields that sustained substantial drought damage leading to early maturation and plant death. Notable aflatoxin contamination appears to be in a small percentage of southeast Nebraska fields, based on samples submitted to several laboratories in the area.
Mycotoxins are common and can be safely consumed at low concentrations. The concentration of aflatoxin that is considered safe for consumption depends on the age and species of the consumer. An abbreviated summary listing the Action Levels identified by the FDA for aflatoxin is listed in Table below.
Testing for Aflatoxin: Farmers and crop consultants can scout high risk fields for Aspergillus ear rot as an indicator for aflatoxin, but only lab testing of grain samples can accurately identify the concentrations of aflatoxin in the grain. Accurate lab test results for aflatoxin will depend greatly on the quality of the sample that is collected and the laboratory methods used to test it. The test results are only applicable to the sample that is submitted, so it is very important to collect an adequate sample for the best results. Refer to the publication, Sampling and Analyzing Feed for Fungal (Mold) Toxins (Mycotoxins) for recommendations on how to collect and submit a high quality sample for mycotoxin analysis.
Contact and submit samples to a laboratory that is certified by the federal Grain Inspection Service and Grain Inspection, Packers, and Stockyards Administration (GIPSA) for mycotoxin analysis for the most accurate results. A GIPSA website lists laboratories certified to conduct testing in Nebraska. They include
- Lincoln Inspection Service, Inc.;
- Fremont Grain Inspection Department, Inc.;
- Omaha Grain Inspection Service, Inc; and the
- Sioux City Inspection and Weighing service Company.
Some grain elevators and individuals may be using a black light (ultraviolet light) to detect for fluorescence as a method for rapid screening of grain samples. This practice is NOT recommended when making decisions about aflatoxin contamination in loads of grain. The component that produces fluorescence under black light is called kojic acid. Although kojic acid is produced by the same fungus that produces aflatoxin, its presence is not necessarily an indicator of aflatoxin and might lead to false positive results and unnecessary rejection of grain.
High Risk Factors for Aflatoxin Contamination in Corn
- Drought-damaged fields, including rainfed (dryland) fields and non-irrigated pivot corners
- Fields or areas with higher incidence of corn ear-feeding insects, such as the corn ear worm
- Grain damaged before or during harvest or after harvest while in storage
Ear rot diseases and aflatoxin are not evenly distributed across fields or in the grain, so scouting and/or sampling should include a substantial portion, at least several acres. The presence of the fungus in kernels does not always correlate well with the presence of aflatoxin, nor does the absence of visible fungal growth necessarily indicate the absence of aflatoxin.Scouting For Aspergillus Ear Rot
- Open husks to view a large number of ears.
- Look for the presence of dusty yellow-green to olive-green spores, especially on the surface of damaged kernels or ear tips (Figure above).
- Pay special attention to higher risk areas.
Harvest and Storage: If fields have documented Aspergillus ear rot and/or risk of aflatoxin contamination, it is recommended that you harvest and keep grain separate from other grain at less risk, such as irrigated fields. Storage of affected grain is not recommended because ear rot diseases and mycotoxins can continue to accumulate during storage. If storage is necessary, cooling and drying grain to less than 15% moisture within 48 hours of harvest will help to slow fungal growth and aflatoxin production. Grain intended to be stored for longer periods of time should be dried to less than 13% moisture.
Presently, it is too early in the harvest to know the extent of aflatoxin contamination in this year’s corn crop, but at this time only a small percentage appears to be affected.
Resources: For more information, refer to the list of publications below or view this week’s episode of Market Journal.
- Plant Disease Profiles #3: Ear Rot Diseases and Grain Molds, EC1901
- Understanding Fungal (Mold) Toxins (Mycotoxins), G1513
- Sampling and Analyzing Feed for Fungal (Mold) Toxins (Mycotoxins), G1515
- Use of Feed Contaminated with Fungal (Mold) Toxins (Mycotoxins), G1514
- Aspergillus Ear Rot and Aflatoxin Production, Iowa State University Integrated Crop Management News
- Check Cornfields for Aspergillus Ear Rot, University of Illinois the Bulletin
| Table 1: FDA action levels for aflatoxin contamination in corn intended for livestock. | |
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| Commodity Action Level | (ppb) |
| Finishing (feedlot) beef cattle | 300 |
| Finishing swine of 100 pounds or greater | 200 |
| Breeding beef cattle, breeding swine, or mature poultry | 100 |
| Immature animals and dairy cattle | 20 |
| For animal species or uses not otherwise specified, or when the intended use is not known | 20 |
| Human food | 20 |
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| Source: FDA Action Levels for Aflatoxin | |
More on Last #Irrigation
It’s been a long irrigation season thus far, but we are so thankful for irrigation in this part of the Country during this drought of 2012! Questions continue to roll in regarding last irrigation for corn and soybeans. Corn at 1/2 starch only needs 2.25″ to finish up so it’s important to know what your soil moisture status is. For most irrigated producers, at 1/2 starch, you should be finished irrigating.
For soybeans at R5 or beginning seed fill, you still need about 6.5″ to finish out the crop. At R6 when the seeds are filling, that drops to 3.5″. At R7 when you begin to see leaves yellowing, that is beginning maturity and you are finished irrigating. They key is we don’t want to fill the profile going into the fall as we’d like to replenish the profile with fall and spring rains and winter snow. However, with soybeans, it’s also critical not to stop irrigating too soon during seed fill.
Gary Zoubek, Extension Educator in York County sheds more light in the following video produced by UNL’s Market Journal.
JenResources 