Justin McMechan - Crop Protection and Cropping Systems Specialist

Corn with wrapped leaves in response to hail
Figure 1. Corn plant exhibiting abnormal growth (wrapped or tied leaves) after being damaged by hail. (Photos by Justin McMechan)

Evaluating Early-Season Hail Damage in Corn May 25, 2017

Factors to consider when assessing early-season hail damage in corn. Growers urged to wait 7-10 days after hail to make full assessment.

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Corn seedlings exhibiting "yellow banding"
Figure 1. "Cross-banding" on emerged corn at SCAL planted on April 17, 2017. Leaves were encased in the coleoptile below ground during the extreme dip in air and soil temperatures. Emergence occurred between May 5 and 10 and was about 50% May 10. Expect plant-to-plant variation in emergence, growth, and development with early-planted corn. (SCAL, May 10, 2017. Photos by Roger Elmore)

‘Cross-Banding’ on Corn Leaves Due to Pre-Emergent, Cold Soil Temperatures May 12, 2017

Early-planted corn at the university's South Central Ag Lab was not emerged during the late-April cold snap, but upon emergence displayed symptoms of “cross-banding”: yellow to pale green, horizontal bands ― perpendicular to the leaf midribs. These often appear in a similar position on other seedlings and at about the same height above ground on different leaves.

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Palmer amaranth
Figure 1. This female Palmer amaranth plant can produce up to 0.5 million seeds.

Watch for Palmer Amaranth in Conservation Reserve Program (CRP) Fields May 12, 2017

Palmer amaranth has not been confirmed in conservation plantings in Nebraska; however, the identification and occurrence of Palmer amaranth in CRP fields in Iowa has raised concerns among weed scientists and growers about its spread into conservation plantings in Nebraska and offer some suggestions for growers.

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Freeze damage to corn seedlings
Figure 1. (left) Yellow corn displaying damage from last week’s frost. Eighty to ninety percent of plants in this area of the field will likely recover, thus replanting would not be justified. Figure 2. Plant displaying frost injury. Both in Lancaster County, May 4, 2017. (Photos by Roger Elmore)

Do I Need to Replant My Corn? May 5, 2017

Considering whether your corn should be replanted? The authors look at types of plant damage at early growth stages and the effect on potential yield. It includes a table of relative yield potential of corn by planting date and population.

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Frost-damaged corn
Figure 1. Buggy-whipping, shown hear in the two plants on the left, is when dead leaf tissue traps new leaf tissue, is one symptom of frost-damaged early season corn. (Archive photo by Roger Elmore)

Risk of Freeze Damage in Early-Planted, Emerged Corn April 28, 2017

Early-season freeze damage results in a range of potential yield impacts. Severe damage is often limited to low-lying areas within a field because cool air is heavier than warm air. Early season survival of corn plants is attributed to growing-point protection below the soil surface; however, a hard frost can penetrate the ground and kill plants. Regrowth of corn following freeze damage is often impeded by dead leaf tissue that can entrap new leaves.

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western corn rootworm beetle

Considering Non-Bt Traited Corn in 2017? Plan for More Scouting February 8, 2017

If you're considering planting non-Bt corn this year, entomologists urge you to plan for the additional pest management practices (and associated costs) you may need to adopt, given this decision.

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Harvest 2016 — When Corn Yields are Below Expectations October 14, 2016

A review of 2016 growing conditions across Nebraska sheds light on a number of factors that may have contributed to reduced yield in individual fields. An understanding of these factors may be helpful when selecting seed for 2017.

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Malformed corn ears
Malformed corn ears

Corn Ear Formation Issues Likely Correlated With the Loss of the Primary Ear Node August 19, 2016

UNL agronomists and educators responding to grower questions surveyed a number of corn fields this week and found a range of corn ear issues: short husks, dumbbell-shaped ears, and multiple ears per node. The article describes and discusses the situation, potential stress agents, and the development of corn. It also encourages growers to check their fields pre-harvest to better assess causes of potential yield loss.

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