June 2015

There is still time for agricultural producers to get involved with the Nebraska On-Farm Research Network's 2015 projects.

Nitrogen Application Based on Maize-N Study

Growers who are interested in sidedressing a portion of fertilizer nitrogen are encouraged to take a look at Maize-N, a decision support tool for N recommendation. Nitrogen management for corn may be improved by applying a portion of N during the growing season.  This allows N fertilizer availability when the crop is rapidly taking up nitrogen.

Maize-N is a UNL computer program that simulates corn fertilizer requirements.  Its nitrogen fertilizer estimate is based on information provided by the user for the current corn crop, last season's crop, tillage, crop residue management, basic soil properties, fertilizer management, and long-term weather data of the field.  The program first simulates corn yield potential and its year to year variation. Based on these user inputs, the program estimates the economically optimal N rate of fertilizer to apply.

This model has been validated in experiments in central Nebraska, eastern South Dakota, and western Nebraska, including both irrigated and rainfed systems. The economic optimum N rate (EONR) simulated by Maize-N and by more empirical university approaches were compared to actual observed EONR. Those simulated by Maize-N were found to have greater accuracy than the university N recommendation approaches. 

This year, the Nebraska On-Farm Research Network is working with a number of growers to evaluate Maize-N.  The study involves two treatments: producer's sidedress nitrogen rate and the Maize-N sidedress nitrogen rate. 

There is still time to get involved with this project and evaluate this tool for nitrogen management.  You can schedule a meeting to go through the Maize-N tool to generate the nitrogen recommendation for your field.  Contact Nebraska Extension Educator Laura Thompson at 402-624-8033 or laura.thompson@unl.edu.  More information about the Maize-N study is available at http://go.unl.edu/MaizeN.

Late Planted Soybean Population Study

Growers also can participate in a late planted soybean population research project.  With consistent rains, many producers still have soybeans to plant or replant. At this point in the season, what would be the recommended seeing rate? Late planted soybeans form fewer nodes per plant resulting in fewer places to set pods.  The thinking has been that increasing seeding rates will compensate for this as well as increase canopy cover and capture more sunlight.

Most universities have suggested increasing seeding rates when planting soybeans in June. However, research done in Iowa showed that soybean seeding rates don't need to be increased as planting is delayed to early June. Previous on-farm research conducted in Nebraska on soybean seeding rates were conducted in April and May. The results suggest that seeding rates greater than 120,000 seeds per acre (with a final stand of 100,000 plants per acre) rarely increase yield.  Is the same true of soybeans planted in June? 

A protocol to test this question was developed by Nathan Mueller, Dodge County Extension Educator.  If you are interested in looking into this question, you can contact him at 402-727-2775 or Nathan.mueller@unl.edu.  The protocol is available at go.unl.edu/latesoybean.

Product Evaluation Studies

Finally, the Nebraska On-Farm Research Network is partnering with industry to research several products available to farmers.

"With so many options on the market, it is important for farmers to evaluate if these products are effective as claimed and if they provide an economic return," says Keith Glewen, on-farm research coordinator.  The studies are designed using randomization and replication so that the effect due to the treatment being studied can be evaluated.

The products being studied include:

• • a seed treatment for Sudden Death Syndrome (soybean),
• • growth promoter (corn),
• • growth stimulator (corn and popcorn), and
• • fertilizer additive (corn).

More Information

For more information and to view detailed study protocols on these topics and more, visit farmresearch/protocols
If you are interested in conducting a study or would like more information, contact your local extension educator, Keith Glewen, kglewen1@unl.edu, 402-624-8005, or Laura Thompson, laura.thompson@unl.edu, 402-624-8033.