Sugarcane Aphid Reported in Tennessee

Doug Johnson, Extension Entomologist, University of Kentucky @DrDougStinkBugs

Dr.Scott Stewart (@BugStewart) has tweeted the first discovery of sugarcane aphid (SCA) in Tennessee (07/07/15) at the AgriCenter in Memphis. The aphids were found and photographed by Drew Ellis. Numbers are low, but this does indicate that the pest is moving up the Mississippi River valley.

Several of our colleagues to the mid-south have commented on the large number of  lady beetles  & larvae that are feeding on these aphids, helping to keep the pest in check. A single insecticide application will stop all that help. Do not apply until absolutely necessary!

Kentucky producers in counties along the Mississippi River and / or counties contiguous with western Tennessee counties are most likely to see this pest.

SCA was not reported in Kentucky in 2014 but was collected in western Tennessee counties and in counties in the Missouri boot-heel. It is not a foregone conclusion that SCA will reach Kentucky, but it is an important enough pest to keep on your watch list.

Grain Sorghum producers / consultants / scouts, that are Twitter followers are encouraged to follow Dr. Scott Stewart, Univ TN, (@BugStewart) along with Dr. Gus Lorenz, Univ. AR , (@guslor77) and Dr. Angus Catchot, MS. St. Univ. (@acatchot). They will be working to manage this problem in their states before the pest gets to Kentucky; if it gets to Kentucky.

KNOWLEDGE IS MONEY!

Considerations for Soybean (Re)Planting in July

Carrie Knott, Extension Agronomist-Princeton, University of Kentucky

Considerable rainfall has accumulated throughout most of Kentucky.  Since June 1 the average rainfall for the Commonwealth is more than 3 inches above normal, with almost 2 inches of that falling in the last 7 days.  There are areas of KY that have received 10 or more inches in the last 3 weeks. Given these conditions many producers must decide whether to plant and in some cases re-plant soybeans once fields dry. 

When considering whether to plant late or re-plant two things come to mind. 

Weed Science Training on Resistant Weeds & New Herbicide Traits

The UK Extension Weed Science Group is conducting a Weed Science Training from 9 am – 3 pm. Two locations will be offered - June 23, 2015 - UK Research and Education Center (Princeton, KY) and June 25, 2015 - UK Spindletop Farm (Lexington, KY).
Please RSVP for lunch count at one of the following locations. UKREC Princeton - (270) 365-7541 ext 264 or email claurent@uky.edu 
UK Spindletop Farm – (859) 257-4898 or email jdgreen@uky.edu  

The Weed Training will cover the following topics: Herbicide Resistant Weeds, New Herbicide Tolerant Crop Traits, Application Stewardship, Herbicide Symptomology, Weed Identification and Cover Crops in Weed Management.
This program will be offered to UK Agriculture and Natural Resource Agents, other UK Agronomists, pesticide applicators, crop consultants, crop producers and agribusiness personnel. Commercial Pesticide Applicator Credits offered 2 general hrs and 2 specific (1A,10 and 12). CCA credits  have also been requested.
For more information, email J.D. Green or James Martin or call (270) 365-7541 ext. 203

Sugarcane Aphid Active in Mississippi…..Not close to Kentucky Yet

Doug Johnson, Extension Entomologist

Several locations in Mississippi (MS) have been identified as having grain sorghum infested with sugarcane aphid. Though it is important to keep up with what is happening, it is also quite important

Kentucky Extension Wheat Contest Forms

Chad Lee, Extension Professor and Agronomist, University of Kentucky

The 2015 Kentucky Extension Wheat Contest forms are available. Entries must be postmarked by July 24, 2015 for eligible entries.

In both 2013 and 2014, Jeff Coke of Daviess County won the tilled division with yields over 120 bushels per acre. In both 2013 and 2014, Duncan Gillum of  Todd County won the no-till division with yields over 115 bushels per acre. The contest also has four area winners:

Corn Nutrient Deficiency from Sidewall Compaction

Chad Lee, Extension Professor and Agronomist, University of Kentucky

This corn field had numerous plants that were stunted with striped leaves. This field was adequate to high in soil test values and had proper pH. When we dug up some plants, we found that the majority of stunted plants suffered from sidewall compaction. Images of the field, the leaf symptoms and the compacted roots follow.

Field where most of the corn appeared yellow with striped leaves.

Cloudy Skies and Striped Corn

Chad Lee, Extension Agronomist, University of Kentucky

Cloudy skies and cool weather can make corn appear deficient.

Leaf striping on corn is being reported across the state. The recent cooler, cloudy weather is probably a big factor in many fields. In these cases, the symptoms are temporary or transient. They are cured by ample sunshine and warmer weather.
Other fields have a legitimate deficiency. Soil testing will identify those deficiencies. A tissue test will likely show a deficiency, but won't explain why it is occurring. A soil test will explain why. If the soil is deficient, then apply the appropriate fertilizer if at all possible. If the soil is test is adequate or above, then wait for the sunshine.
While pulling the soil test, dig up a few roots. Sidewall compaction can lead to these symptoms as well. I'm sure no one reading this post "mudded-in" corn. But your neighbors may have! Feel free to pass this along to them to check for sidewall compaction. If they have sidewall compaction, there is not much they can do. Sidewall compaction is a field where they should cut their losses and move on.
Here are some previous articles on corn leaf striping.