Research and Development

Research & Development

ASK THE DOCTOR-
AN INTERVIEW WITH
DR. FREDRICK MILLER,
Research Horticulturist with
Joliet Junior College & The Morton Arboretum

Q. How long have you been doing Horticultural Research?

	A. I have been involved in the Midwest professional green industry over the last twenty years. I have conducted research on pests and plant problems as well as looking for sustainable solutions to the common and uncommon challenges of growing plants.

Q. How did you get started in horticulture?
Q. How did you get started in horticulture?

	A. I got my Masters degree in Horticulture from the University of Arkansas and a Ph.D. from Iowa State University. Then I joined the University of Illinois Extension Service and began working with the Morton Arboretum and Dr. George Ware. This work he continues with Dr. Susan Wiegrefe during the summers when I am not teaching horticulture at Joliet Junior College. My classes there include entomology, arboriculture, soils and introductory horticulture.

Q. We first met when you wanted to use our nursery to conduct pest control studies using summer oil, how did that turn out?

	A. We were studying the efficacy and phytotoxicity of lite summer oils sprayed on woody plants. As a result of some of this work (conducted at McHenry County Nursery and published in the Journal of Environmental Horticulture in 1994) summer oils have become an industry standard as a relatively non-toxic treatment approach for a wide variety of pests on a wide variety of plants.

Q. You have been involved with the Emerald Ash Borer in Illinois, what is going on there?

	A. One of my primary research interests in conjunction with the Morton Arboretum is the Emerald Ash Borer (EAB). We have brought many agencies together to formulate a proactive plan for its eventual arrival. We are working with the Illinois Department of Agriculture, the USDA and Dr. Appleby at the University of Illinois to monitor sites across the state and be on top of any EAB if/when it is found. I cover the northeastern Illinois section that includes forty different communities and forest preserves and seven nurseries across three counties.

Q. What other areas of research are you involved in?

	A. We are conducting research on pest resistant Elms, Japanese Maples, Carpinus, Lindens and Poplars. The tests run through a variety of pests (such as cancker worms, Elm leaf and Japanese beetles, leaf miner and gypsy moth) on selected host plant types. Another major area of study in the last few years is being conducted with an Iowa State graduate student on the natural deterrents and detractants (such as leaf chemistry or leaf pubescence).

Q. How does your research affect our customer?

	A. The most important thing for landscape contractors is to stay informed about the pests in your area. We are constantly monitoring for numerous pests and posting the information on our website. Then make sure you know where your plants are coming from and how they got here. It's critical to know who the grower is of the plants and whether they have had a certified inspection.

Q. What can we/our customers do? How do we identify EAB?

	A. Check out the websites and know what to look for in your landscapes and woods around you. Watch for sudden dieback in Ash, which will be easy to spot this year as we’ve had fewer hot/dry summer days which usually bring on Ash decline (though many trees recover). If you purchase plants out of state, make sure you examine them upon arrival and make sure to get certificates of inspection — better yet, don't purchase from out of state sources. Make sure you know where your plants are coming from and how they got here. It's critical to know who the grower is of the plants.

Q. Finally, we have noticed a lot of different physiological plant behavior this year in landscapes all over the Midwest, what happened?

	A. Trees and plants endure a smorgasbord of environmental conditions. Every year the seasons bring us different weather. Although it meant spring field work went without a hitch, the very dry March and April we had left the trees wanting for moisture during the important time of leaf expansion.
	In April plants are growing rapidly in the lengthening days and rising temperatures. The leaves are producing hardiness inhibitors to allow for greatest growth. They have little ability to acclimate or resist extreme changes in the environment.
	Of course, every plant goes through this tender stage during the springtime, but not all plants are at the same stage when extremes hit. Not only were the elms’ leaves expanding during the driest period, but then we had a late freeze in May! We had not had enough warm temperatures to stimulate the acclimation properties of leaves and they got hit hard. Some leaves browned and crumbled off completely.
	But true to its hardy form, the elm cultivars bounced back and quickly put out another flush of leaves, of more normal size and vigor. These were then hit with the flea weevil leaving shothole damage in elm leaves in some locations of the Midwest (if they had pumila or parvifolia in their cross).

	Conditions during the growing window this year were also favorable for anthracnose and other leaf fungal diseases because of the wet cool May and June. Arborvitae reacted with a heavy seed set to the early dryness but seem fine now.

	This spring for example was a great trial on the elm cultivars. And we are happy to say they are passing this test with excellent grades. If you were to look at the elms as our fall begins, they seem to be a tree that can withstand much of what nature throws their way. We think the Morton Arboretum hybrids will be a great asset to any landscape, city or suburban, street or park.

Links for more information:

Morton Arboretum Plant Health Care Report
Chicago Botanic Garden
Emerald Ash Borer