The Daves are touring the north central region scouting for soybean aphids. They look at buckthorn every spring and fall. You might be (or should be?) wondering why they were looking for soybean aphid when most of the beans in Iowa aren't planted or haven't emerged yet. They are scouting for aphids on buckthorn, the overwintering host of soybean aphid. Yes, their primary host is a woody shrub commonly found in shelter belts around the north central region. They move to their secondary host, soybean, every summer. Their life cycle is complicated and I won't go into details here, but they want to learn more about their movement between the primary and secondary host.
Dave Voegtlin explained how he searches for soybean aphid on buckthorn. Photo by Thelma Heidel-Baker.
Dave Hogg and Matt O'Neal hoping to find aphids. Photo by Thelma Heidel-Baker.
Close-up of buckthorn, note smooth leaves with reduced venation.
Thelma was practicing her photography skills.
Although we spent some of the morning looking around the ISU campus (there is a LOT of buckthorn on campus because there used to be a breeding program!), we did not find any aphids. Sniff sniff. They did find aphids at previous stops before Iowa and I tried using a special camera lens to take close-up photographs.
Dr. Voegtlin giving me a camera tutorial. It is actually difficult to take pictures of very small animals! Photo by Thelma Heidel-Baker.
My best photo shows a few soybean nymphs on a buckthorn plant.
Seeing these aphids on buckthorn is kinda like seeing a unicorn. I've worked with soybean aphid since 2001 and have NEVER seen spring colonies on buckthorn. So this was a special work day for me - thanks to the Daves for stopping by today!