Indiana Department of Natural Resources sent this bulletin at 08/09/2023 08:40 AM EDT
Weekly Review for August 9, 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.
Ren Hall (Nursery Inspector & Compliance Officer) - RHall@dnr.IN.gov
The Indiana State Fair is still going on until Aug. 20, but remember it is closed Mondays and Tuesdays. Come see us at our invasive species booth in the DNR building and check out our butterfly garden.
I wanted to share a picture of a bald-faced hornet nest I took in a nursery last week. I was about 3 feet away when I noticed it. Luckily I didn’t get stung since these wasps do defend their nests when you get too close. This one had insects actively flying in and out as I watched. Bald-faced hornets don’t reuse their nests year to year, and they should be left alone if not in a high-traffic area. They are mostly predators of other insects and can act as pollinators when searching for nectar later in the season, so there is no reason to harm them if they aren’t harming you.
Over the last couple of weeks I’ve come across several populations of green June beetles and witnessed an interesting behavior that they are known for. I’ve heard large numbers of them buzzing like bumblebees through tall grass. It almost sounds like a bee or wasp nest nearby until you spot these large beetles flying around. I’ve also found them attracted to the lights on my house at night.
The Indiana State Fair is in full swing and you never know who you might meet with a visit to the DNR Building. Last weekend, inspector Kallie Bontrager and K-9 Epic spent some time talking with visitors about DEPP’s use of specifically trained canines to help sniff out new locations of spotted lanternfly.
For those dealing with tulip tree scale, now is the time treat in central Indiana. This pest can also attach magnolia trees. I saw the first signs of crawlers at the end of last week. The treatment window is quite short.
I have noticed several nurseries with hefty populations of pine needle scale (Chionaspis pinifoliae) on Scotch pine (Pinussylvestris). These "armored scales" spend most of their life cycle under a hard protective covering. Armored scales feed by inserting their long piercing-sucking mouthparts into plant tissue to slurp-up the contents of ruptured plant cells. In the images below, you can see both mature and immature females attached to the needles.
I found a triangulate cobweb spider (Steatoda triangulosa) nest at my house this past week and a corresponding large pile of pillbug carcasses underneath the web! This is a common spider in Indiana and not venomous to people.
I’m also sharing some photos of browning boxwood. There are many reports this year of browning boxwood from across the state. This is due to cold/freeze injury that occurred earlier in the year. The Volutella fungal pathogen is frequently found in conjunction with this type of injury. The Purdue Landscape Report has a great summary of this problem and fungal pathogens affecting boxwood.
