Integrated Crop Management News

As flood waters recede, the renovation of flooded pastures is just beginning. Now is a good time to check pasture plants for survival. Forage production is a function of the plant species, and their density and growth. Evaluate live plants (plant vigor), plant density, and desirable species versus weeds.

Iowa’s most significant soybean insect pest, soybean aphid, has host-alternating biology. This species has multiple, overlapping generations on soybean in the summer and moves to buckthorn in the winter. Fall migration to buckthorn is based on senescing soybean, and decreasing temperatures and photoperiod. For the majority of the year, soybean aphids are cold-hardy eggs near buckthorn buds (Photo 1).

Over the last five years, the North Central region of the U.S. has been responsible for 82 percent of the nation’s soybean harvest. Due to the region’s importance to soybean production for its various uses in feed, biodiesel and other widely used products, the North Central Soybean Research Program (NCSRP), through funding from the Soybean Checkoff Program, has sponsored on-farm surveys to farmers in the region to evaluate trends in farming practices and management systems.

Flood waters are receding, but the challenges in recovery for farmers and livestock producers are just beginning. We recommend producers get out in their fields as soon as possible to assess the damage to pastures and hay ground, then check out possible disaster assistance. Look for three things in the assessment: debris, silt on the forage, and thinned or dead forage plants.

Reports of winter injury in alfalfa fields are coming in across the state. Old man winter along with other management factors can take a toll on alfalfa stands. Older stands, stands that were harvested between mid-September and late October, and stands with minimal stubble appear to have suffered the worst winter injury. Additionally, in many fields it is obvious where the snow drifted and provided insulation and protection as those parts of the field are the greenest.

Planter maintenance is important for all farmers, particularly those in reduced and no-till systems. A well-maintained planter gives seed its best chance, and with field operations happening in a shortened timeframe this spring, planer maintenance will be as important as ever. Most of the physical responsibility for manipulating soil, placing seed, and getting the seed off to a good start rests on the planter.

You know what they say: March comes in like a lion and out like a lamb.

Well, it certainly feels like this past winter was just one extended lion. While there were signs that maybe Iowa would be seeing greener pastures, that has not been the case, especially for farmers who have experienced flooding this past month. With the recent incidents and resulting disaster proclamations, as well as lost grain storage, the idea of farming greener pastures has a long way until fruition.

Farmland in Iowa, western Illinois, and eastern Nebraska is experiencing flooding issues. Planting in these areas may be delayed or may not be planted to any crop in 2019. This can have significant economic and environmental consequences if flooded fields are left barren. Long-term damage to soil needs to be considered when planning for this year’s or next season's crop.

Spring weather has finally arrived and fieldwork will begin soon. Iowa State University research suggests cereal rye should be terminated at least 10-14 days prior to planting corn, so the favorable weather forecast may allow some farmers to begin terminating overwintered cover crops in the next few weeks.

How did alfalfa fields fair this past winter? This is a complicated subject since several factors play into alfalfa winter survival. These factors include fall soil moisture conditions, 4-inch soil temperature, and other stresses like stand age, soil fertility, and fall stubble.

The rapid snowmelt in Spring 2019 has caused instances of stored grain being covered with floodwater. By current Food and Drug Administration (FDA) policy, grain inundated by uncontrolled river or stream water is considered adulterated and must be destroyed.

Because of limited fall 2018 anhydrous ammonia fertilizer application, fertilizer infrastructure including transportation, distribution, and application may be stressed this spring. A review of application equipment considerations can help ensure that your nitrogen fertilizer is properly and safely applied. This article focuses on anhydrous ammonia equipment.

With the short timeframe for fieldwork this spring prior to planting, early weed management may fall to the bottom of the priority list for many.  For those who have persistent issues with winter annuals (field pennycress, horseweed/marestail) in no-till, an early burndown treatment may be worth the extra effort this spring.  Winter annuals resume growth soon after the arrival of warm temperatures, so as soon as fields are fit the weeds will be susceptible to spray.

Several physical and chemical reactions take place following anhydrous ammonia injection: dissolution in water, reaction with soil organic matter and clay, and attachment of ammonium ions on the soil cation exchange complex. These reactions all tend to limit the movement of ammonia, with water having the greatest initial effect.

It was a late harvest in fall 2018. Soils were wet and frozen when it was time to apply anhydrous ammonia. Those situations resulted in much less than normal anhydrous ammonia application last fall. Therefore, considerable anhydrous ammonia needs to be applied this spring. There is only so much capacity to switch from one nitrogen (N) fertilizer product to another.

On-farm trials are an easy way for farmers to learn how practices, products and equipment will work in their cropping systems. The concept of on-farm trials has been around for decades, with farmers placing rows or strips of different practices within their fields for comparison. On-farm trials are easier to conduct now with assistance from formalized on-farm trial programs and the use of GPS and precision technologies.

The above-average snowfall and potential for significant rain events this spring could present challenges during the upcoming planting season. These conditions, on top of excessive soil moisture last fall that may have led to compaction and soil damage during and following harvest, have farmers concerned about completing spring tillage, fertilizer and planting operations in a timely manner.

Producers wanting to add to or improve the forage species in their existing pastures should typically consider using either the frost seeding method in February and early March, or interseeding later in the spring months. This has been an unusual end to the winter, so as soon as the snow melts, frost seeding can begin.

The amount of snow we received and potential spring rain events can be challenging to an early start to the growing season. Approaching field operations for N applications, tillage, weed control, etc. need to be weighed against potential soil compaction and successful seed germination.

The two bu/acre Iowa corn yield reduction (from the previous 2018 report) shown in the February 9 crop report demonstrated the impact of late-season wet weather. Corn quality and potential food safety issues are also determined late in the growing season. According to data recently completed by the Iowa Department of Agriculture and Land Stewardship (IDALS), levels of the mycotoxins deoxynivalenol (also known as vomitoxin) and zearalenone are elevated in this year’s Iowa corn crop.&