Indiana Department of Natural Resources sent this bulletin at 07/28/2021 07:31 AM EDT
Weekly Review for July 28, 2021
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.
Spotted lanternfly (Lycorma delicatula) was found in Indiana for the first time in Switzerland County this month. This is the farthest west the insect has been found in the United States. This federally regulated invasive species has a detrimental impact upon plant growth and fruit production, especially in vineyards and orchards.
A homeowner in Vevay contacted us with a picture that was taken outside his home of a fourth instar larvae. DEPP staff surveyed the site and discovered an infestation in the woodlot adjacent to a few homes in the area. The site is within 2 miles of the Ohio River and the Markland Dam. DEPP and USDA are conducting an investigation to determine exactly how large the infestation is and where it could have come from, as well as how to limit the spread and eradicate the population.
More information about spotted lanternfly can be found on our webpage.
Photo 1 - Spotted lanternfly adult (Photo by Angela Rust)
Ken Cote (Nursery Inspector & Compliance Officer) - KCote@dnr.IN.gov
Last week I was complaining about all the rain. Now, I could use a half inch. Things are drying up quickly at my garden. The high humidity levels and hot temperatures are causing the development of many diseases. Leafspot are going crazy on my tomatoes. Squash vine borer and squash bugs are killing my zucchini and gourds, but surprisingly have not touched my cucumbers yet. I am also starting to see early stages of Pseudocercospora leaf spot on my tree lilacs. This is becoming more of an issue along with leaf spot on Yoshino cherries. Once again, I am getting premature leaf drop on my Yoshino cherry. I am also getting leaf drop on my serviceberry. I love this tree, but every year I get leafspot disease and I am also seeing hawthorn lace bugs feeding on the leaves. Lace bugs will cause course stippling type damage which can lead to leaf browning. Adults, nymphs and fecal spots can be found on the undersides of leaves. Slime molds are growing on my mulch and encircling the stems of some of my perennials. This looks terrible but usually does not cause any plant injury. I have not seen any leaf spot development on my river birch yet. I am sure something else will be declining in my yard next week.
You would think I would have a perfect garden being a plant inspector. This is not the case. Sometime conditions are very favorable for the pest or pathogen and unfavorable for the plant. This makes any type of control difficult. There are years in which certain plants perform wonderfully in my garden and the next year that same plant does not. It is very weather dependent. However, if you have a problematic plant, you may want to have a timely treatment program in place or just remove the plant and replace it with something that requires less input. This may be difficult for some clients to accept, especially if there is emotional attachment to the plant.
Ren Hall (Nursery Inspector & Compliance Officer) - RHall@dnr.IN.gov
The past couple of weeks the main thing I’ve been seeing is red headed flea beetles in nurseries, both adult beetles and their feeding damage. Damage seems worst on weigela and hydrangeas. I’ve also seen damage on sweetspire, holly, hibiscus, dogwood, oak, ninebark, and many other ornamental plants. They don’t necessarily do significant harm to the plant, but the distinctive feeding damage can be unsightly as seen on this ‘Rubidor’ weigela.
I am getting some inspections done now that it has stopped raining. Bees are slowing down honey production. Dutch clover is still blooming. Honey production is reported to be below average right now. This is likely due to the cold May weather and all the rain in June and July. We need some nice clear dry days for bees to get out and collect nectar.
Soybeans have started blooming. Some varieties of soybeans produce a good amount of nectar. The problem with soybeans is the insecticide applications to control soybean aphids. These insecticides will also kill bees. If you are a beekeeper in these areas with insecticide applications, you need to talk with farmers within a mile to let them know you have hives in the area. Give them your contact information so they can contact you. Protect your bees if they must spray. Registering on driftwatch.org will also help pesticide applicators be aware of your hives and know how to contact you if they are spraying.
If a beekeeper does get sprayed, they need to contact the Office of the Indiana State Chemist Pesticide Section. A regional pesticide investigator will conduct an investigation and file a report. This is the first step to getting reimbursed for losses.
