Indiana Department of Natural Resources sent this bulletin at 04/26/2023 08:07 AM EDT
Weekly Review for April 26, 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.
The spotted lanternfly infestations in Huntington and Switzerland counties have been keeping us busy over the winter and spring. We launched a billboard campaign in cooperation with Purdue University in northern and southern Indiana and handed out yard signs to spread awareness. Kallie Bontrager, our inspector out of LaPorte, has been training her Australian shepherds to “sniff out” spotted lanternfly egg masses.
We’ve attended industry trade shows and held public meetings to inform the green industry and homeowners about the insect and our management efforts. Over the last couple of months, we’ve been scraping egg masses at both locations with a total of 14,870 destroyed. Each egg mass contains an average of 40 eggs, so we’re hopeful we’ve been able to put a dent in the number of nymphs that will hatch in the coming weeks. We’ll continue scraping until hatch begins, and then switch our strategy to treating trees to further reduce the population through the spring and summer. A trapping survey is also being planned at the infested locations as well as high risk locations around the state.
During the spring and summer please let us know if you think you may have seen spotted lanternfly by contacting us at 866-NO-EXOTIC (866-663-9684), or by email at DEPP@dnr.IN.gov. Please be sure to provide your contact information and detailed information about the location. Early detection is crucial to successful spotted lanternfly management efforts.
Eastern tent caterpillar hatched here in Perry County sometime the week of April 3. I also noticed a little carpenter bee activity that started about the same time. Dogwoods are in bloom. We have had weekly rains and night temperatures last night dropped down into the mid 30s – so it’s definitely spring in southern Indiana!
This past week I was able to get out and take a look at some dealers. I found some blackberry with orange rust, columbine leaf miner, various aphids, and crown gall. I also observed quite a few root problems.
I also want to remind beekeepers that if you have not taken the Bee Informed Partnership Survey that you still have until the end of the month to complete it. Last year we had a total of 110 beekeepers take it. The more people we can get to take the survey the better picture we will have regarding the state of beekeeping in Indiana. It only takes about 20 minutes to fill out so if you have some time I would urge you to take a look.
This week while scraping for SLF egg masses I came across a small swarm of springtails. It was a magical moment because look at these cute little guys!
Springtails are not insects themselves but more like cousins. Insects are in the class Insecta whereas springtails belong to the class Collembola. I really like springtails because they can be a type of indicator species. They prefer moist, healthy soils when found outside which is a good sign, however, they can also be a pest when found in a kitchen sink or bathtub suggesting a humid living situation. I think an interesting idea that this hexapod brings up is that the term “pest” is entirely from a human perspective. Some food for thought while we admire this buggo (informal term for arthropods).
I never used to see boxwood leafminer in nurseries, but I’ve found it twice already this spring. The popularity of Green Mountain and Green Velvet, two cultivars that are particularly susceptible, is partially to blame for the progression of this pest. It’s tough to time applications on adults, but a systemic applied shortly after bloom can be quite effective on the larva. That should be soon.
Ken Cote (Nursery Inspector & Compliance Officer) - KCote@dnr.IN.gov
Not much pest activity in my region. I did see one spot of eastern tent caterpillar in the Morgan-Monroe State Forest last week. Unfortunately, the infestation was along the interstate and I was not able to get a good picture. The big issue this week will continue to be damage from winter injury and the freeze we experienced earlier this week. It was 25 degrees at my house a couple of days ago. I will likely see a lot of damage in my landscape. The boxwoods on my property were hammered from winter injury and boxwood leafminer. They were just starting to grow out of the damage and will now likely experience spring injury on top of the issues they were already having. Bloodgood Japanese maples are not leafing out correctly due to winter injury. I am observing this on specimens that have been in the ground for more than 20 years. Interestingly, my lace-leaf Japanese maples were looking good prior to the frost and actually fared the fluctuating winter temperatures better than the Bloodgood did. This is opposite of what I would have expected.
I have conducted some inspections at greenhouse and nursery dealers that are receiving plants from out-of-state sources. During one I found leaf spot on Pieris. I occasionally see this problem. There are a number of leaf spots that can infect Pieris. Aphids and thrips were found in greenhouse environments. I also was at a greenhouse that had an abundance of shore flies, but not really many fungus gnats. Shore flies look similar to fungus gnats, but a close look will reveal some differences. Fungus gnats are more mosquito-like in appearance. The larvae of fungus gnats can feed on the fine roots transplant and promote the spread in infection of pythium root rot. Shore flies are a nuisance and thought not to cause serious harm to plants. They feed primarily on algae but can be an indication that conditions in a greenhouse are too moist.
During a greenhouse inspection I also found a zebra swallowtail adult flying around. I do not typically see these until later in the summer. They are not a common butterfly, so it is always fun to catch a glimpse of one. This one was landing on potting media long enough to allow me to get a decent picture. Photographing this insect is like photographing bald eagles. They are out there, but often do not cooperate when it comes to getting a decent photograph. I hope to have more fun stuff next week.
