DNR - Entomology Weekly Review, June 12


Weekly Review for June 12, 2018

Indiana Department of Natural Resources
Division of Entomology & Plant Pathology
Phone: (317) 232-4120
Our Website
Inspector Territories

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. 

Links can be found at the bottom of the page to manage your subscription to this list. Comments and questions about this report are welcome and can be sent to Eric Biddinger or to your respective Inspector.

Vince Burkle (Nursery Inspector & Compliance Officer) - VBurkle@dnr.IN.gov

I conducted inspections in Wabash County and also assisted with a group inspection in southern Indiana last week. There are not many new things to report from Wabash County. Apple scab is becoming worse on crabapples. Maple mites were a little more abundant, but the rain we had over the weekend might slow them down. I also found eriophyid mites on bur oak, potato leaf hoppers on almost everything, and oystershell and cottony maple scale on ‘Sun Valley’ maple.


Ken Cote (Nursery Inspector & Compliance Officer) - KCote@dnr.IN.gov

Now it’s raining! Maybe in a few weeks I can tell you how many root rot issues I am finding. I received reports of Japanese beetle activity in the Bloomington area from some landscapers. I have not personally seen them yet, but they are obviously emerging early this year despite the cold spring. Bagworms are starting to cause noticeable damage on evergreens in many landscapes. You should be treating infestations now to prevent serious damage from occurring. I have seen white pine weevil damage in Serbian spruce, Norway spruce and white pine. Look for wilting leaders. Close inspection will reveal small exit holes, frass, chip cocoons or even larva inside the leaders. Prune out and destroy heavily infested leaders. The best time to control this pest is to treat adults before they lay eggs. Timing is always tricky on this one and once you see the damage it is really too late to spray.

Leafhoppers have also been very abundant during the last week and seem to be causing more damage this year compared to other years. I found leafhoppers on red bud, red maple, Fothergilla and oaks. Look for the coarse stippling on many hosts and on red maple you can also see leaf cupping and stunted growth. Maple mite populations are continuing to increase and I have seen noticeable damage on Autumn Blaze maples. I have also seen a few small infestations of fall webworm on oaks and sweetgum in Monroe and Greene Counties. Look for webbing occurring on the outer ends of branches. Small infestations should be pruned out of infested tress.  


Cedar apple rust continues to be found sporadically on susceptible host. Last week I found a great example on Brandywine crabapple. I am still not seeing widespread or severe apple scab infections so far this year. However, it is still early in the growing season. I found needle cast symptoms on Serbian spruce in Owen County. Samples were taken to see if needle cast could be confirmed in the lab. I also found symptoms of Nectria canker underneath the tree wrap on a crabapple tree in a garden center. Nectria can appear as multiple orange spots on the trunks of trees. It often can infect stressed hosts. I do not often come across this pathogen, but have seen it on occasion. I am continuing to see spot anthracnose on flowering dogwood, but I have not seen any Discula anthracnose this year. However, I did find symptoms of anthracnose on blueberries in Brown County.  


Kathleen Prough (Chief Apiary Inspector) - KPrough@dnr.IN.gov

I helped with a group nursery inspection last week in southern Indiana. I found one Japanese beetle already out and eating on a leaf. I did see tulip tree scale on some of the tulip trees. One tree that was heavily infested had wasps, flies and ants all over it. The noise from the wasps and flies at this tree made me look closer for what could be there to attract them. 

Most beekeepers who ordered nucs from Indiana beekeepers picked them up last week. They may have to supplement these nucs with sugar water to get them to draw out the comb. The dry hot weather in May slowed the nectar flow down last week. With the rain we received this weekend, hopefully the plants will start to produce nectar again. Indiana nectar flow is usually till the end of June. With this year’s crazy weather, we will have to watch and see. 

The Beekeepers of Indiana have their summer meeting this Saturday, June 16 at the Purdue Bee Lab. The entire day will be spent in hives learning more about bees. If anyone is interested they can go to http://www.indianabeekeeper.com/ to check out the agenda and location. Bring a hat and veil with you.

FieldWatch Inc. has been around for 10 years now. It was originally created as DriftWatch by Purdue University in 2008 to help protect specialty crop growers from pesticide drift. FieldWatch is now in 18 states and a Canadian province and provides an online national registry for specialty/sensitive crop growers and beekeepers. Beekeepers can register for free at BeeCheck.org. This allows commercial applicators intending to use insecticides to locate local hives and communicate with the owners. Once notified, beekeepers can take action to protect their hives, if necessary. If there is a pesticide drift problem, beekeepers should call the Indiana State Chemist Office at 765-494-1582 to investigate.

Angela Rust (Nursery Inspector & Compliance Officer) - ARust@dnr.IN.gov

I’m sharing a couple of photos that I took last week. One photo is of native lady beetles working hard on some aphids on mandevilla. There were actually quite a few native lady beetles on this group of potted mandevilla. Always good to see our beneficial insects doing their thing. The second photo is of maple spindle gall on Sugar Maple. These galls are caused by the feeding of an eriophyid mite.


Jared Spokowsky (Nursery Inspetor & Compliance Officer)Jspokowsky@dnr.IN.gov

I've seen quite a bit of interesting things lately.

The great bagworm hatch has begun as noted previously but this past week I saw something that I had never seen in person. I was doing an inspection in a nursery and came across an arborvitae which had a heavy bagworm infestation. I found the typical bagworm damage to the foliage but I also noticed the bark at the top of the trees looked a little strange. Upon closer inspection you could see where the bagworm had peeled the outer bark off the trees.


I also saw some Austrian Pine with a fairly heavy case of Dothistroma needle blight. I can usually find this on Austrians but I have also had this confirmed on Norway Spruce which shows similar symptoms but less pronounced.


I also saw European sawfly on Austrian pine. I can usually see damage from sawfly at some point during the season but I don’t always catch them in the act. A lot of growers who know what to look for and are actively looking for them can have a hard time finding them. Usually I don’t see a great deal of damage and they are not worth treating unless you find a really large outbreak.


At first I thought this was cottony maple scale but I had never seen it on the leaves. After doing some research Cottony maple scale Pulvinaria innumerabilis is only found on the twigs and branches while Cottony Maple Leaf Scale Pulvinaria acericola lays their eggs on leaves.

I found leaf miners on Boxwood, Magnolia, Sweetgum, English Oak, and Alders.

Lastly, I will close with another milestone which flew down the back of my shirt. 


P.S. you don’t always have to look at trees and bugs while doing inspections. 


Kristy Stultz (Nursery Inspector & Compliance Officer) - KStultz@dnr.IN.gov

While doing inspections in Delaware and Madison counties this last week, I noted a heavy infestation what appears to be Willow Blister Gall on Pussy Willow. These mites spend the winter on the bark and branches and in spring move to the developing leaves. While the damage is unsightly, it is not usually harmful to the overall plant health. I also noted what is probably white pine weevil damage. The tops of the 6’ tall trees are just beginning to show decline and death, but there were obvious signs of infestation.


No reports this week

Megan Abraham (Division Director & State Entomologist) - MAbraham@dnr.IN.gov

Eric Biddinger (Nursery Inspector & Compliance Officer) - EBiddinger@dnr.IN.gov 

Eric Bitner (Nursery Inspector & Compliance Officer) - EBitner@dnr.IN.gov

Kallie Bontrager (Nursery Inspector & Compliance Officer) - KBontrager@dnr.IN.gov

Ren Hall (Nursery Inspector & Compliance Officer) RHall@dnr.IN.gov

Phil Marshall (State Forest Health Specialist) - PMarshall@dnr.IN.gov

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