Matt and Erin have a special guest on this podcast to help understand life cycle assessments. Dr. Kurt Rosentrater is an engineer and associate professor at Iowa State. Kurt explained the basics of conducting a life cycle assessment, including assumptions and resulting complications that come with this tool. They focused on a recent example looking at environmental impacts in four major crops. Here is the link to the paper so you can follow along with figures: http://www.ingentaconnect.com/content/iop/erl/2015/00000010/00000009/art094016. The assessment showed freshwater ecotoxicity impact in soybean increased 3-fold from 2002 to 2012. The authors claimed the insecticides used to control soybean aphid was an important factor. Corn, cotton and wheat did not have a significant increase of impact over the study duration. Learn more about Kurt's research and teaching program here: http://www.abe.iastate.edu/kurt-a-rosentrater-assistant-professor/.
Today in this podcast, Matt and Erin talk about a new publication summarizing insecticide evaluations for soybean aphid. The Yellow Book for soybean aphid starting in 2005 in response to a growing demand to manage this invasive pest. Matt was up for the challenge and passed the torch to Erin in 2009. Now the evaluations are at 2 ISU Research Farms and include 25+ treatments annually. You can access all the Yellow Books FREE on their lab website: http://www.ent.iastate.edu/soybeanresearch/content/extension.
Today, Matt talks about a "farminar" with PFI (Practical Farmers of Iowa) he recently recorded. It was about neonic seed treatments in soybean. Watch the archived version here: http://practicalfarmers.org/farmer-knowledge/farminar-archive/neonicotinoid-seed-treatments-are-they-necessary/. Then Erin mentioned Pollinator Fest this summer is happening on Saturday, June 25 in Ames. But the majority of the time was spent interviewing an incoming post-doc, Matt Kaiser. He will start in Matt's lab this summer and work on a new parasitoid wasp that attacks soybean aphid. He reviews wasp biology and talks about how this new tool can help suppress soybean aphids in Iowa.
To start this podcast, Erin recaps current growing degree days in Iowa for 2016 and how they are really different than in 2014. Visit her blog post to see some cool graphs: bit.ly/1nO0ZDd. Matt recently attended a soybean entomology working group meeting and recapped some of the highlights. Specifically, he talked about pesticide use comparisons around the U.S. and the possible introduction of Bt soybean in the U.S. market.
Soybeans are going into the ground, and Matt and Erin have started a new podcasting season. They talk about early-season soybean pests, like black cutworm and bean leaf beetle, and the likelihood of seeing injury this year. Read more about the predicted cutting date for black cutworm here:
http://crops.extension.iastate.edu/cropnews/2016/05/black-cutworm-scouting-advisory-2016. They also spend some time highlighting some new people and research projects going on this summer. Finally, Matt talks about a recent publication that looks at the probability of breaking even with different inputs.
In this episode, Matt and Erin talk about upcoming events, pest activity updates and research projects. Erin is organizing a Corn Insects Workshop on July 29. Learn more and register here: http://www.aep.iastate.edu/feel/insect.html. There is a 50-person cap, so register now if you want a space! Erin had several reports of pea aphid in alfalfa, but most farmers decided to cut instead of spray. Learn how to identify aphids in alfalfa here: http://crops.extension.iastate.edu/cropnews/2016/05/aphids-showing-alfalfa. Erin also saw a few aphid mummies in clover and they both experienced honeydew dripping from a tree on campus this week. Matt talked a bit about planting conditions for his wasp and bee projects, noting compaction and crusting in some commercial soybean fields.
Today, Matt and Erin have so much to talk about in this episode. The multiple phone calls and people stopping by Erin's office can't stop the podcast. Lab members found a few soybean aphids in central and northeast Iowa. This is not too surprising because a few soybean aphids can usually be found in June. Populations are very low, but something to note as the field season continues.
The first soybean aphids of the year were found in northeastern Iowa. Photo by Greg VanNostrand.
The warm winter was helpful to those insects trying to overwinter in Iowa, particularly for bean leaf beetle. For the other crop in Iowa, corn rootworm egg hatch is peaking, stalk borers are moving to corn, and European corn borer egg hatch is also happening now. Then the conversation turned to millipedes - not a typical field crop pest. They talk about field conditions conducive to millipede injury, in addition to other emerging pests like slugs, snails and isopods. Finally, Matt reminded us Pollinator Fest is coming up at Reiman Gardens in Ames on June 25.
Random fact: Millipedes are arthropods within the class Diplopoda. They are distant relatives to insects and arachnids. People who study millipedes are called diplopodologists.
Millipede. Photo by David Cappaert, www.ipmimages.org.
Today, Matt and Erin talk about current pest activity in Iowa. Specifically, the last week was very hot (>90 degrees) and that isn't conducive for soybean aphid growth. So no new detection since the last podcast (but not surprised because aphids don't do well under consistently hot temps). Also, some alfalfa farmers are starting to see potato leafhopper injury. Matt heard about early twospotted spider mite injury in Illinois and that is a concern for extended hot and dry periods. Southeastern Iowa is abnormally dry right now and so be looking for initial spider mite infested along edge rows. Mite injury should not be confused with herbicide injury that is also starting to show up in some soybean fields. Finally, Erin and Matt talk about Pollinator Fest displays at Reiman Gardens. Erin will have the kids make Wikki Stik insects and Matt has prepared a honey tasting station.
Potato leafhopper (Photo by Marlin Rice) and classic "hopper burn" (Photo by Purdue Extension). To learn more about potato leafhopper, read this ICM News article.
Twospotted spider mite (Photo by Frank Peairs) and spider mite injury (Photo by Whitney Cranshaw). To learn more about scouting for twospotted spider mite, read this ICM News article.
Wikki Stik insect art for Pollinator Fest (Photo by Erin Hodgson).
Don't drought this episode was a good one. Matt shares an update on the Iowa drought and encourages people to use the U.S. Drought Monitor as a tool to measure landscape moisture levels. Matt and Erin transition and talk about pest activity around the state, starting with twospotted spider mite. Erin wrote a recent ICM News article that talks about scouting and managing this pest that favors hot and dry conditions. Spider mites can be first detected around field perimeters and then eventually infest the field interior. Discoloration, webbing and stunted plants are often the result of heavy spider mite feeding. Erin mentioned a new miticide, AgriMek, that has promise for suppressing mites in corn and soybean; find the label here. The conversation switched gears to talk about some corn silk clipping pests, like Japanese beetle and corn rootworm adults. Scouting to determine pest densities and potential interference with pollination is important. Learn more about Japanese beetle ID, scouting and management with an ICM News article.
Twospotted spider mite. Photo by Frank Peairs, www.ipmimages.org.
Bean leaf beetle. Photo by Marlin Rice.
This podcast episode focuses on a few recent pest updates, like soybean aphid, twospotted spider mites, and a mix of defoliators. Matt talks about spider mite activity in some of his research plots and also in fields near Brookings, SD. Erin notes soybean aphid activity is down throughout Iowa and they both revisit the economic threshold for this common pest. To read more information about why the economic threshold for soybean aphid remains consistently at 250 per plant, read this webpage co-authored by many university entomologists. Finally, Matt shares a research update on the release of parasitic wasps that like to feed on soybean aphid.