Indiana Department of Natural Resources sent this bulletin at 06/25/2019 07:25 AM EDT
Weekly Review for June 25, 2019
This informal report by the Division of Entomology and Plant Pathology is designed to update the Nursery and Greenhouse industry of insect and disease pests the Division has been encountering on a week to week basis and as a way to give a “heads up” of things to be on the lookout for. Comments and questions about this report are welcome and can be sent to your respective Inspector.
Ren Hall (Nursery Inspector & Compliance Officer) - RHall@dnr.IN.gov
I only had time for a single quick dealer inspection this week. The most interesting thing I found was pretty severe early blight (Alternaria solani) on tomatoes, with a confirmed diagnosis from PPDL. The plants were yellowed and drooping, with heavy leaf spotting. Leaf spots were brown, many with concentric rings like a fried egg.
Other finds were rust on apple trees, bagworm hatchlings on white pine and every other nearby plant, a mating pair of white-margined burrower bugs, bacterial leaf spot on Annabelle hydrangea, and my first Japanese beetle adult of the year.
The Beltsville Bee Lab published an article on a possible treatment for Nosema ceranae in honey bees. Nosema ceranae can be an unidentified problem in hives. If a hive dies, I like to send off a sample of the dead bees to have Beltsville Bee lab test for Nosema. If a hive is weak, a beekeeper could send in samples of bees to have tested also.
There are two types: Nosema apis and Nosema ceranae. N. apis has been around for a long time while N. ceranae was identified in the USA around 2006. We do not have a treatment for Nosema in live hives. Fumigation or irradiation will kill both Nosema and American foulbrood spores in used equipment. Iotron in Columbia City can do irradiation, but you have to have 500 boxes to be treated before they will shut down their line. This is not inexpensive, so not too many beekeepers do this.
There are some management practices the beekeeper could do to lower the risk. One is to replace any frames that have honey bee fecal material on them. Rotating out 2 -3 frames yearly can help reduce Nosema spores.
One article from UC Davis I read said that N. ceranae could be susceptible to cold weather. Putting frames with comb in the freezer may kill N. ceranae along with all stages of wax moths and small hive beetle. Sunlight is an effective control for N. apis. I have done this. I took the frames outside in the sunlight then put them in a chest freezer. The trick is not to put too much stuff in the freezer so you can get the super full of frames in it.
