Integrated Crop Management News

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Begin Scouting for Black Cutworm in Corn

May 11, 2021
Estimated black cutworm dates for each Iowa crop reporting district based on peak flights during April.

Black cutworm (BCW) is a migratory pest that arrives in Iowa with spring storms each year. It is sporadic and unpredictable, making it essential to scout to determine whether BCW larvae are present in a field and management is required. Since much of the corn planting around the state is complete and many fields have emerged, now is a good time to begin scouting for larvae.

Adjusting Weed Management Plans After The Dry Start

May 11, 2021

Performance of preemergence herbicides in many areas of the state may be less effective than normal due to limited rain following application. Although weed emergence following planting was reduced by dry soils and cool temperatures, it is likely that most fields will have some weeds that emerged during this period. Systematic scouting of fields, beginning shortly after crop emergence, will be essential to determine how best to manage weeds throughout the remainder of the season

Take Care When Washing Work Clothes Used Around Pesticides

May 10, 2021
graphic showing different washing instructions

Pesticide applicators and handlers need to wear, at a minimum, the Personal Protective Equipment (PPE) specified on pesticide product labels. Most pesticide labels require a long-sleeved shirt and long pants. Proper laundering of work clothes that may be contaminated with pesticide residues is essential to reduce pesticide handlers’ short- and long-term exposure to pesticides and prevent the potential of residue cross-contamination onto other clothing. 

Estimating First Crop Alfalfa Harvest using PEAQ

May 5, 2021
PEAQ table

The growth and development of alfalfa is affected by many factors, including temperature, soil moisture, stand age and even cultivar. Alfalfa growth has been slower than normal due to cool conditions in April. This is a good reminder that using a calendar date to determine when to harvest the first crop of alfalfa may not the best method. In order to accurately predict the optimal time for the first cutting, the University of Wisconsin developed the Predictive Equations for Alfalfa Quality (PEAQ) method.

High Mortality Rates for Bean Leaf Beetle in Northern Iowa

April 21, 2021
bean leaf beedle

Bean leaf beetle adults (Photo 1) are susceptible to cold weather and most will die when air temperatures fall below 14°F (-10°C). However, they have adapted to winter by protecting themselves from harsh temperatures under plant debris and loose soil. Each spring, adult beetles emerge from their overwintering habitat and migrate to available hosts, such as alfalfa, tick trefoil, and various clovers. As the season progresses, bean leaf beetles move to preferred hosts, like soybean.

Termination Timing of Cereal Rye Cover Crop for Improved Weed Control in Soybean

April 20, 2021
tractor planting in cover crop

Current cooler weather conditions are posing challenges for growers with a cereal rye cover crop to get it terminated. However, for growers planning to plant soybeans into the rye cover crop, there may be a perk to letting the rye cover crop accumulate more biomass. That perk being the cover crop biomass can help with weed suppression. The ability of cereal rye to suppress weeds is directly related to the biomass accumulation at the time of termination.

Spring Forage Management Considerations

April 16, 2021

Pasture and forages stands have really started to green-up. Here are some fertilizer and weed management considerations and recommendations to help make the most out of pasture and forage stands this year.  

Fertilizer considerations

Fertilization is just as important for forages as it is for row crops to maximize productivity. However, current fertilizer prices may have you seeing a lot of dollar signs.

Phosphorus, potassium, and lime considerations

To terminate or not to terminate?

April 15, 2021

Current cool temperatures increase the risk of failures in terminating cover crops. While cereal rye continues to grow during these conditions, activity of herbicides is reduced. Translocation of glyphosate to growing points is reduced under cool temperatures, slowing activity and increasing the potential for control failures. It is generally recommended to avoid applications when nighttime temperatures fall below 40 F, and we prefer temperatures at application to be at least in the mid-50s with clear skies.

Check FieldWatch® Before Pesticide Applications

April 15, 2021

Prepare for a safe pesticide application season by checking the FieldWatch® registry before making pesticide applications. The FieldWatch® registry provides easy-to-use, accurate, and secure online tools to enhance communications and awareness between crop producers, beekeepers, and pesticide applicators.FieldWatch® features a voluntary mapping tool through Google Maps™ that shows pesticide applicators the locations of registered sensitive crops and beehives so they can make informed decisions regarding pesticide applications.

Alfalfa Weevils Active throughout Southern Iowa

April 12, 2021

Adult alfalfa weevils become active and start laying eggs as soon as temperatures exceed 48°F. Like other insects, the development of alfalfa weevil depends on temperature, and we can use accumulation of growing degree days (GDD) to predict activity. Alfalfa weevil egg hatching begins when 200-300 GDD (base 48°F) have accumulated since January 1.