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Showing posts from March, 2019

Updates to corn nitrogen guidelines in Minnesota

By: Daniel Kaiser, Extension specialist, and Fabian Fernandez, Extension specialist
The corn nitrogen guidelines recommended by the University of Minnesota have recently been updated to include data from 2017 and 2018.

The current guidelines use the Maximum Return to Nitrogen (MRTN) approach, which relies on a database composed of corn nitrogen response trials conducted across the state. The recent update includes the addition of 24 new sets of data for corn following soybean and 10 for corn following corn.

The table below summarizes the revised N rate values. The addition of the new data resulted in a slight increase in the amount of N suggested for both corn/corn and corn/soybean rotations.
Guidelines for use of nitrogen fertilizer for corn grown following corn or soybean when supplemental irrigation is not used (2019) Corn/CornCorn/CornSoybean/CornSoybean/CornN price/Crop 
value ratioMRTNAcceptable RangeMRTNAcceptable Range0.05  195 lbs. N/acre 175-210 lbs. N/acre 150 lbs. N/acre 1…

Insects and the Polar Vortex: How will soybean aphid fare in 2019 after the cold winter?

Anthony Hanson, Extension Post-doctoral associate and Robert Koch, Extension entomologist
On January 31, 2019, most of Minnesota had morning lows near or below -30°F (Figure 1). Cold winters help prevent many potential pest insects from establishing here or requires species that cannot survive our winters like potato leaf hopper or black cutworm to migrate up from southern states. Extreme cold can also knock back species that are established here.
Insect cold tolerance For the most part, insects match the temperature of their surrounding environment, making them "cold-blooded."  Wind chill doesn't really affect them, but air temperature does. Even so, many insects can survive temperatures well-below freezing due to their own antifreeze compounds like glycerol. 
Similar to weather forecasting, insect forecasting can give us a general idea of future insect populations. The minimum winter temperature can help forecast freeze mortality.
Where insects overwinter also affects…

Respirators: How to comply with WPS, navigate fit testing liability, and keep your employees safe

Wearing a respirator is critical for using certain pesticides safely. Under the Worker Protection Standard, employers of pesticide applicators are required to provide annual fit testing and respirator training to employees. The UMN Extension pesticide safety team has heard concern from employers about navigating WPS requirements and the liability that could accompany fit testing. In response, we've created a series of respirator fit testing workshops. These workshops are free and hands-on. Topics include:

Respirator selectionHow to conduct a fit testResources for respirator trainingResources for written respiratory protection plansRecommendations for navigating liabilityChange-out schedules for filters / cartridgesRespirator maintenance

These workshops run from 8:30am - approximately 1:30pm, and lunch will be provided. The ideal audience for these workshops includes co-op health and safety managers, company managers, and rural healthcare providers, but all are welcome! 
Farmers are…

Nutrient Management Podcast: Phosphorus and potassium application in a late spring

In this episode, Dan Kaiser, Lindsay Pease, Melissa Wilson, and Jeff Vetsch discuss phosphorus and potassium application in a late spring. Should growers be concerned when applying P and K if soils are wet? Is it better to delay planting and get fertilizer applied? Are there options to apply P and K post-planting?

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Support for this project was provided in part by the Agricultural Fertilizer Research & Education Council (AFREC).

Reading the tea-leaves of alfalfa winter injury

M. Scott Wells and Roger Becker - University of Minnesota

Predicting alfalfa winter injury or kill is never easy. There are suites of stressor impacting winter injury or kill where some under our control (e.g., harvest management, stand age, etc.) and others that are not (e.g., weather). The essential takeaway regardless of the stressor is to evaluate your alfalfa stands every spring, and ask the question, “Will my alfalfa meet my forage demands?” This will help you determine which management steps are best relative to forage demands and alfalfa stand health. Following is a quick overview of critical elements that can impact alfalfa winter survivability and subsequent performance.

How previous management affects winter injury The ability of alfalfa stands to overwinter starts with optimal management decisions. Alfalfa cultivars must be selected by regional and climatic specificity to ensure the appropriate genetics are present for winter hardiness and disease resistance. Proactive fer…

Spring fertilizer decisions: What are the top considerations?

By: Dan Kaiser, Extension specialist

After a fall when planned fertilizer applications could not be made, tough decisions need to be made in spring. Planting at the optimum time is crucial to ensure optimal yield potential for corn, and waiting to apply fertilizer can result in significant delays to planting. Options for applications post-planting are more limited with nutrients which do not move in the soil. While nitrogen and sulfur can be broadcast on the soil surface and incorporated by rainfall, that option is not ideal for phosphorus or potassium. To reduce the risk of delayed planting, there are several considerations to ensure planting is on time while maintaining optimal availability of phosphorus and potassium.
Are the nutrients needed? Soil tests help assess whether the soil has the capacity to supply adequate phosphorus and potassium. The greatest risk for yield to be limited by phosphorus, potassium, or zinc is when soils test Medium or lower. Prioritizing fields with Me…

Post-planting management of nitrogen

In this episode, Dan Kaiser, Fabian Fernandez, Anne Nelson, Greg Klinger, Brad Carlson, and Jeff Vetsch discuss post-planting management of nitrogen. How important is nitrogen applied prior to planting? What options are available to farmers to apply nitrogen at or after planting? Should inhibitors be included? Thank you to the Minnesota Agricultural Fertilizer Research and Education Council (AFREC) for their support of this podcast.

Learn how to write a preharvest grain marketing plan

Successfully marketing commodities in times of low prices is one of the top ways a producer can generate a higher margin. However, determining when and how to market a crop with current low prices is challenging.

Grain farmers and agri-business professionals attending this educational session will:
learn how to write a pre-harvest marketing planreview pricing toolsparticipate in a hands-on game simulation Two workshop locations remain: March 13 --Murray County Fairgrounds 4-H Building, 3048 S. Broadway Ave., Slayton, MN 56172, start time 1:00 p.m.March 20 --Belle Plaine Vets Club, 221 North Meridian Street, Belle Plaine, MN 56011, start time 1:00 p.m.. These workshops are free thanks to sponsorship by Minnesota Corn Growers Association.

For more information, visit Preharvest grain marketing plan workshops.
Contacts: Colleen Carlson (traxl042@umn.edu) and Melissa Runck (mkrunck@umn.edu).

Manure research update: Sidedressing swine manure into corn

By: Melissa Wilson, Extension manure specialist
Key pointsWe sidedressed finishing swine manure into corn with a dragline hose system and compared it with other sidedressed nitrogen sources: anhydrous ammonia and liquid urea-ammonia nitrate.Corn grain yields at harvest were similar across all nitrogen treatments. Finishing swine manure appears to be a viable nitrogen source for sidedressing manure. We will continue this study next year to see if we get similar results. What we did In an on-farm experiment near Le Sueur, Minnesota, we tested several nitrogen sources for sidedressing corn. Our primary goal was to see if finishing swine manure could be used and if it could be applied with a dragline hose system.

Initially, the corn was planted in early May with approximately 40 pounds of nitrogen applied with the planter. We sidedressed the corn in early June in large strips (about 24 rows), when the corn was at about the V4 growth stage. We aimed to get it applied before the growing poi…

Phosphorus and potassium application in a late spring

In this episode, Dan Kaiser, Lindsay Pease, Melissa Wilson, and Jeff Vetsch discuss phosphorus and potassium application in a late spring. Should growers be concerned when applying P and K if soils are wet? Is it better to delay planting and get fertilizer applied? Are there options to apply P and K post-planting? Thank you to the Minnesota Agricultural Fertilizer Research and Education Council (AFREC) for their support of this podcast.