Matt O'Neal talks with Amy Asmus of Asmus Farm Supply to discuss outbreaks of aphids in cornfields around north-central Iowa. The two discuss what species of aphids are in corn and what impact they may have. Be prepared for more questions than answers as the scientist and crop consultant compare notes about this problem. For a more complete description of the aphids see Dr. Erin Hodgson's article in the Integrated Crop Management Newsletter (www.extension.iastate.edu/CropNews/2009/0807hodgson.htm)
Soybean aphid populations reach threshold in Iowa and japanese beetles are becoming an increasing problem for both soybean and corn. In this episode we discuss both of these pests and the need to scout now to determine the need for an insecticide. To learn more about Japanese beetles see Dr. Hodgson's latest article in the Integrated Crop Management newsletter (http://www.extension.iastate.edu/CropNews/2011/0722hodgson.htm).
As soybeans reach the late reproductive stages the need to manage aphids decreases. However, aphids persist in soybean fields around the midwest. We discuss a couple factors that should be considered when applying insecticides this late in the year. Also, we re-count the spread of Japanese beetles in Iowa as a new herbivore of soybeans.
Matt and Erin summarize the trend in soybean aphid populations for the midwest. They discuss other pest, include the corn rootworm and the reports of cornfields damaged by this pest. For more info on why this may happen in Bt-corn fields see http://bit.ly/16plxWm.
Also, for more info about how rotating crops is good for more than just managing rootworms, visit http://www.sustainablecorn.org/
Although soybean aphid has been a relatively low threat this year, drought conditions have been a perfect storm for spider mites. We encourage people to scout fields now to fully protect yield.
Today, Erin is so excited to tell everyone about her new, 12-page publication called, "Getting to Know the Insects." This publication is geared to youth and new agronomists that want to learn more about how to identify, sample and management field crop insects. It's available for $2 in the ISU Extension Store. Next, Matt and Erin talk about corn and soybean switching to reproductive stages around Iowa and implications for pest scouting and management. In particular, hot and dry weather favors twospotted spider mites, but expected cooler temperatures can promote soybean aphid populations. Erin also mentions a rare pest, redheaded flea beetle, showing up in a cornfield this summer. Read Erin's blog to see feeding injury on corn leaves. Erin also mentioned some upcoming field days at the ISU FEEL demo lab located between Boone and Ames, Iowa. The first is the Crop Management Clinic (13-14 July), which features a number of different topics related to crop production and protection. The second is an all-day workshop on corn insects (29 July). We aren't sure why, but there are a lot of references to MMA fighters in this episode??
Redheaded flea beetle on soybean. Photo by Lewis Veith.
In this episode, Matt and Erin start off with talking about the hot weather in Ames. A local rain shower will help lawns and crops. Erin shared some updates on soybean aphid in Iowa. A few more reports are showing up from the lab as they visit various research farms. The percent infested plants is higher than in the past few years, so scouting in highly encouraged this summer. Both have noted aphids around the yard and on campus this month, too. Matt wants to try out a new segment called F.I.T. (fun insect trivia). He asked me about how the malaise trap was named and Erin was kinda right. Erin also had a F.I.T. about determining the sex of Japanese beetle. It wasn't nearly as interesting as Matt's story and maybe not even that important to know. Erin also noted Japanese beetles are emerging in southern Iowa and corn rootworm egg hatch is peaking around Iowa this week. If you live in north-central Iowa, plan to attend a field day at the ISU Northern Farm near Kanawha.