Indiana Department of Natural Resources sent this bulletin at 07/05/2017 10:41 AM EDT
Weekly Review for July 5, 2017
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.
Division News
The 2017 Invasive Forest Pests Early Detector Trainings hosted by Purdue and the DNR are coming up fast. Learn to recognize and report invasive forest pests at these two-hour meetings. There are more than 80 people currently registered. Reserve your spot for Bloomington (July 11), Aurora (July 12), or Nashville (July 13) by registering online. Pesticide CCHs, ISA CEUs, and SAF CFEs will be available.
Tar spot is forming on Norway Maples this week. It starts as a yellow area with black dots. The dots eventually become large, black lesions on the upper surface of the leaf.
In a first for me, I found a small amount of what looks like Quince Rust on the fruit of a European Mountain Ash. While most common on hawthorn, this fungus is not unknown on quince, pear, cotoneaster, serviceberry, and mountain ash.
Other finds this week include an uptick of spider mite on roses, swamp milkweed, maples, and arborvitae and Oak slug sawfly feeding. I also found a persistent mealybug population in a greenhouse related to a single, old display plant. While enjoying the 4th of July in Akron, I spotted some significant yellowing of leaves in a backyard tulip tree. Closer examination revealed a heavy tuliptree aphid population.
This week showed the first Japanese beetle showing up. I have found them on Hollyhock, Rose, Peony and Hydrangea. I found flea beetle and Four-lined plant bug on Weigela, Salvia and hydrangea. The main diseases I have seen have been Powdery Mildew on spirea, lilac, Salvia and London Plane tree. Several varieties of Peony had Botrytis blight.
I conducted the first flight of the annual aerial survey to detect and map forest damage. This flight was primarily to detect Gypsy Moth Defoliation, if any, across northern Indiana. The flight started in Porter County checking treatment sites from last year and this year, plus possible locations reported by landowners and DNR staff. The flight covers the lake shore to the Michigan Line and then across northern Indiana, through South Bend, Elkhart, Goshen, Kendallville, Pokagon State Park and the northeast corner of the state, and returning through Fort Wayne, Whitley County, Kosciusko County (Pierceton).
I did not detect any defoliation at any treatment site or at locations reported by landowners and staff. The landowner reported sites had light defoliation that is only noticeable from the ground.
Flying from Bloomington, I mapped EAB mortality west of the 2016 locations as I flew to Porter County. The advancing front of ash mortality from EAB is now slightly west of U.S. HWY 231 from Spencer – Greencastle – Crawfordsville – Lafayette and then on a line northwest from Lafayette to Wheatfield in Jasper County. So the movement westward is not as much as in prior years which maybe from a reduced amount of ash or that mortality is at a very low level now but will increase in 2018.
Not finding Gypsy Moth defoliation in northeast Indiana during the flight, I also noticed that the woodlots/forests in northeast Indiana no longer have standing dead ash trees. Looking at those woodlots/forest now, you do not realize EAB mortality was there. I also noticed that the standing dead ash in northeast Indy/Fishers area, where EAB first occurred, are all on the ground.
Additional flights will cover southern Indiana looking for EAB mortality, Chestnut oak mortality, location of tree of heaven and any other forest damage.
Bees are still bringing in nectar. The rains have helped the plants to keep producing nectar. Some beekeepers took off honey in late June while some were lucky to take honey off at the end of May. You can take off the full caped honey frames now, extract it, and put them right back on the hive to see if they will fill them up again. Other beekeepers will just leave the frames on and put another honey super on top for the bees to fill up.
This has been my year to get the bees to draw some new comb. I have been getting rid of some old comb and making the girls draw out new. By feeding them lots of sugar water, the bees will use it to drawn comb while useing the nectar they bring in to feed their young. So we feed until enough comb is filled out for the bees to be able to store enough food for the winter.
My strongest hive did great, drawing out 5 new honey supers. The swarm I got has been drawing comb as well. Swarms are great for drawing out foundation. I’m still feeding them to get a third deep drawn out. Sugar water is still on the other two hives with one more honey super for them to draw out. Most likely I will only take honey off my strong hive. The other three, I will have to see. I would rather leave them lots of honey for the winter than take it.
More people are going to one size boxes for brood and honey supers. You can do all deeps, all mediums, all shallow supers or mix and match. Many are choosing all medium supers (only 6-5/8” high). Some are also doing 8 frame boxes. It is up to the beekeeper. The advantage to having all the same size boxes is that you can move frames of honey up out of the area where the queen is laying and give them a frame with new foundation or a drawn comb frame with open cells. Take a frame of brood from a strong hive and give to a weak hive.
Another reason for going with only mediums, shallow or 8 frames is they are lighter to lift. A deep 10 frame box full of honey can weigh as much as 80 pounds. That can be hard to take off the hive and put back on. Taking one off, I will let gravity take it down to the ground. Putting it back on is the hard part. I have lifted them in one swoop and drop it on top of the hive. Most of the time I let the beekeeper put it back on. Following is an article that coves why people are using the different size hive boxes: http://www.beeculture.com/deeps-mediums-shallows-decisions-decisions-decisions/
I keep debating about going to one size. I have mostly shallow supers and keep using them. Two shallow supers equal one deep. Usually I have one deep and the rest shallow supers. I like to have a shallow super on the bottom, the deep super next and the rest shallow. With having a screened bottom board (for Varroa mite control) the queen will sometimes not go all the way down to the bottom of the frames. Too much light coming in with the screen open. By having a shallow super on the bottom, the queen will use all of the deep super just above the shallow super on the bottom. If she goes down to that bottom super, that is good. My swarm hive though is an exception. I had put them in a deep nuc box that I had before putting them in a regular hive. So this hive has a deep, two shallow and a deep on top. I will leave it this way until next year when I could split the hive or switch the boxes around. I could also use the frames to replace old ones in the other hives.
I like to tell beekeepers to replace about 3 frames out of the brood area per year. This is to decrease the buildup of disease spores in the hive. It also lets you pull out frames that were not drawn out correctly. The thing is the beekeeper should think a year ahead what frames they want to replace. Come August the beekeeper can go through the hive and find the frames they want to replace next year. These frames can be put in frame position 1 or 10 (outer frames). Come May there is less likelihood of there being brood on these frames so it is easy to pull out and replace.
I’ve been seeing small populations of Japanese Beetle adults around, but have not seen areas with much damage yet. I’ve included a photo of a Swamp White Oak leaf with primarily Tubakia leaf spot damage, but also some Oak Anthracnose. When we have a lot of moisture in the spring, these fungal pathogens can cause greater damage to leaves. I also found some peach trees with a lot of sap oozing and a few tiny borer holes. Due to the large amount of sap ooze, I am thinking these trees likely had a canker disease as well as ambrosia beetles. Both can be common problems on peach trees, and both can cause sap ooze – but generally the amount of sap ooze with ambrosia beetles is smaller. Canker disease can cause significant sap ooze. I also found some plant bug damage on Forsythia, traces of Fig Rust on Miss Figgy Dwarf Fig and ‘shot hole’ type leaf spots on English and Cherry Laurels.
