Indiana Department of Natural Resources sent this bulletin at 03/28/2023 07:50 AM EDT
Weekly Review for March 28, 2023
This informal report by the Division of Entomology & Plant Pathology is a commentary on insects, diseases, and curiosities division staff encounter on a week-to-week basis. Comments and questions about this report are welcome and can be sent to your respective Inspector.
Well, we got that cold snap I was afraid of. I have seen more than a few flowering trees (especially peaches) that arrived from southern nurseries in bloom. If they were not sheltered, they are probably toast.
I was helping a grower with timing for white pine weevil. The guideline is to treat at about 20-50 Growing Degree Days (GDDs) base 50⁰. So, I was a little surprised to see we are still at zero despite the previous warmups. This might be one insect that will run a week or so behind last year. Michigan State’s GDD Tracker is an easy-to-use source of GDD data and models for common turf pests, too!
I was called the other week about a hive that was dwindling fast and had signs of dysentery. The beekeeper feared it was a Nosema infection and worried they would need to euthanize the hive and destroy the equipment. I told them I did not think that was necessary and instructed them to collect a Ziploc bag with 50 or so bees so I could test them. After crushing a 15-bee composite sample, I put them under the microscope and could not find a single Nosema spore.
When reviewing the photos I was sent, it appeared that there were large amounts of sugar dripped on the top bars. After talking with the beekeeper, they confirmed that the sugar board had basically “melted” and dripped down through the hive. I highly suspect that excess moisture dripping on the colony was the cause of the collapse. I can’t say what caused the dysentery, but it was likely due to a nutrition issue.
