Ask Rosie!

Posted on May 01 2017 in Backyard

We received several questions for Rosie Lerner, our gardening expert, for our May issue. Here are just a few of the questions, and her answers, that appeared in our magazine.

Photo by iStock/Getty Images Plus

Tall trees

DNR maintains state tree registry

We have a huge sycamore tree on our property – we guess it is probably around 100 feet tall. Our neighbors think this might be the largest sycamore in the state. Does anyone keep track of tallest trees in Indiana? How can I find out if mine is a record-holder?

— R.C., Marion County, Indiana

The Indiana Department of Natural Resources maintains the Indiana Big Tree Register, and you can see the records online at The official register considers the total height, the trunk circumference at 4.5 feet above the soil line, and the average spread of the crown. The current Indiana champion sycamore is listed as 122 feet tall.

Information on how to measure your tree, as well as instructions for nominating a tree for the Register is available at

How to get soil samples

We are interested in getting soil samples from our garden to improve soil quality this year. Where is the best place to go to learn how to do this and submit samples?

— Joe and Marilyn Walton, West Lafayette, IndIana

You are wise to consider soil testing for your garden! Purdue Extension bulletin HO-071, Collecting Soil Samples for Testing, teaches you how to take soil samples for testing. It is available at

Purdue also maintains a list of certified soil testing laboratories at

Killing beetles without hurting bees

My flowers are being eaten by the Asian beetle. How do I get rid of these underground beetles? We also have bees. Is there a way to rid myself of these hungry beetles without killing our bees?

— Louise Howard, Wheatfield, Indiana

I applaud your concern for protecting bees! It is difficult to know which specific insect pest is in question, as there are a number of “Asian” beetle species. The control strategy will depend on a conclusive identification. Since you mention that they are underground, I wonder if you are talking about Japanese beetles. The adults chew on foliage and flowers, while their larvae (white grubs) feed on plant roots.

Purdue Entomology Extension provides an overview of identification and control in publication E-75, Japanese Beetles in the Urban Landscape, and includes a number of options that are less likely to harm bees. It is available at

Also, see Purdue Extension publication POL-1, Protecting Pollinators in Home Lawns and Landscapes at

Mystery volunteer could be ironweed

Photo contributed by Richard Downs

This plant (photo at right) came up in my backyard last summer. It grew to over 13 feet tall. I would like to know if you can identify it.

— Richard Downs, Lanesville, Indiana

That is an impressively tall volunteer! It is difficult to tell much detail in the photo about the flower structure, but considering the size, stem color and foliage, one possibility would be giant ironweed, Veronia gigantea. While this plant commonly reaches up to 10 feet tall, rich soil in garden conditions can result in taller plants.

Giant ironweed is a native species, and there are some cultivars in the trade. Did you observe purple flowers as the plants progressed? Have a look at to see if this looks like your plant. If not, and if the plant returns this year, you might consider submitting a sample to the Purdue Plant and Pest Diagnostic Lab.

Rosie Lerner is the Purdue Extension consumer horticulturist and a consumer of Tipmont REMC. Have a question about gardening? Use the form to send it to us. Or, questions about gardening issues may be sent to: “Ask Rosie,” Electric Consumer, P.O. Box 24517, Indianapolis, IN 46224, or