Integrated Crop Management News

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Cold Temperatures and Burndown Herbicides

April 11, 2016
Frost damaged giant ragweed seedlings

The weather forecast appears to be favorable for field activities so people will be anxious to get into the field. A concern for many will be the effect of the widespread freeze on the performance of burndown herbicides. Unfortunately, there is no simple blanket statement that can be made since the plant response will vary depending on weed species, weed size, and the herbicides used.

2015 Evaluation of Commercial Seed Treatments on Soybean at Three Locations in Iowa

April 4, 2016
ICM seed treatments tables

The percentage of soybean treated with a seed treatment has increased greatly in recent years. Over the past five growing season, the Robertson lab has evaluated the effect of commercial seed treatments on stand count, disease incidence and severity, and yield of soybean with funding provided by Iowa Soybean Association.

Fine-Tune Oat Seeding Rate This Spring

March 28, 2016
Oat Seedlings in the field

It’s time to plant small grains. When planting oats, spring wheat, and barley, farmers typically plant two to three bushels of small grains per acre, but there is a better way to optimize plant populations and grain yields. Farmers calculate corn and soybean rates by seed count and should do the same for small grains. Several factors affect final plant stands at oat harvest, including: desired final plant stand, number of oat seeds per pound, germination rate in the seed lot, and expected stand loss from irregular seeding depth or early plant death.

Terminating Cover Crops - What's Your Plan?

March 22, 2016
Cereal Rye

Take time now to get a plan in place for terminating a cover crop. Whether termination will be done with a herbicide, rolling/crimping, or tillage, it is important to know not just the advantages, but also the limitations with a termination method. Regardless of termination choice, it is important to have a plan in place to minimize problems this spring.

Dicamba and Dicamba-Resistant Soybean Varieties

March 18, 2016

On February 3, 2016, Monsanto announced commercial launch plans for soybean varieties resistant to dicamba and glyphosate (designated Roundup Ready 2 Xtend varieties). This announcement followed China’s decision to approve grain from these varieties for import. Many weed management practitioners hope the use of this new technology will improve control of challenging weeds, including those with evolved resistance to glyphosate and herbicides from other groups.

Approaches for Managing Corn Rootworm in Iowa

March 16, 2016
Corn Rootworm injury

Corn rootworm is a persistent and economically important pest in Iowa, with yield loss caused primarily by larval feeding on corn roots. Genetically modified corn with Bt traits kills western and northern rootworm larvae, and Bt-rootworm corn has been available since 2003.

The Source Matters for Getting the Most out of Aerial Imagery

March 10, 2016
Aerial Imagery photo

As spring plans are finalized, don’t forget to consider aerial imaging as part of a continuous improvement plan. Remote sensing and the use of aerial imagery has been used for decades in agriculture but since 2010 we’ve seen the number of available imagery providers grow extensively. The use of imagery can vary from farm to farm but several common uses include variable rate fertility recommendations, assessing water management performance, quantifying soil compaction and machinery induced yield limiters, locating late season weed outbreaks, and generally evaluating the consistency of crop vigor across a field. 

Selecting Nozzles for Postemergence Herbicides

February 15, 2016

An earlier ICM News article discussing affects of nozzle type and size on spray coverage prompted a question from a farmer regarding nozzle selection. In recent years there have been many advances in nozzle design. The primary improvement has been development of nozzles that minimize the formation of driftable droplets (< 200 micron) while still producing a droplet spectrum that provides the level of coverage required for consistent, postemergence weed control.

Managing Two Soybean Pests to Optimize Yield

February 11, 2016
Effectiveness of Aphid-resistant soybeans graph

Soybean cyst nematode (SCN) and soybean aphid (SBA) are important soybean pests in the north-central region. Soybean varieties with host plant resistance for SCN (PI88788) and SBA (Rag1) can suppress pest populations and subsequently protect yield. In addition, seed treatments are becoming widely adopted and now can include a nematicide, fungicides and insecticide. Combining host plant resistance with seed treatments could potentially further protect yield.