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Plant diseases diagnosed – Audio

Brian Hudelson, Sr. Extension Outreach Specialist
Plant Diagnostic Lab
Department of Plant Pathology
UW Madison College of Agricultural and Life Sciences
(608) 262-2863

IMG_0140-e14582431483323:04 – Total Time
0:18 – Welcome to the UW Plant Disease Diagnostic Lab
0:37 – How the lab works
1:01 – Everyone may use the lab service
1:37 – Plant diseases common in Wisconsin
2:34 – Visit the web site
2:54 – Lead out


Sevie Kenyon – A visit to the University of Wisconsin plant diagnostic lab, we’re visiting today with Brian Hudelson, Department of Plant Pathology, University of Wisconsin-Extension in the College of Agricultural and Life Sciences, and I’m Sevie Kenyon. Brian, very generally, tell us what the plant diagnostic lab is.

Brian Hudelson – Basically, I do diagnosis of plant diseases on virtually every plant you could imagine. The only thing I don’t work with is turf and so I see samples of field crops, forage crops, ornamental, you name it and I probably see it.

Sevie Kenyon – And can you describe for us, Brian, how it works?

Brian Hudelson – So if you have a sick plant and kind of want to know what’s going on, you submit a sample to us. You can submit it though you county extension office or submit it directly to my lab. We take a look at it, decide what we think might be the problem, we can do some lab tests, and then once we figure out what the problem is, you get a written report back in the mail and recommendations on how to manage the problem.

Sevie Kenyon – Brian, what kind of samples do you get and who do they come from?

Brian Hudelson – They come from a lot of different places. I think the majority of the samples that I get typically are ornamental samples, so a lot of woody ornamentals. We do charge a small fee for what we do, so people, if they are concerned about ornamentals, will be willing to pay for a diagnosis on a tree or a shrub. Probably about 50-60% of our samples are ornamentals of some kind or another. We get field crops and forage crops. We also get vegetables and fruits. Those are lesser amounts; probably about 10% of my samples are in each of those particular categories.

Sevie Kenyon – What kinds of diseases are common here to the state of Wisconsin?

Brian Hudelson – We do a lot of testing for Oak wilt, that’s a big one on Oak tress.  A lot of folks are concerned about that. It can really range a lot; root rots, leaf spots, and blights. We get a lot of samples that come in on tomatoes. We do free testing actually for late blight for tomato and so folks can send in a tomato sample and if they invoke the words late blight we’ll do a free diagnosis for them whether its late blight or not. We do a lot of soil testing, actually as well. Pea root rot testing, so if there is a canning company that wants to contract with a grower to grow peas on their property this coming year, they’ll bring in a sample to us, we grow peas in the greenhouse, and then we report back about whether that particular field is a good candidate for pea production. We do a lot of testing for soybean nematodes in collaboration with a faculty member here in the plant pathology department and also some folks over in the agronomy department as well.

Sevie Kenyon – And Brian, if people are interested in using your service or learning more, what should they do?

Brian Hudelson – They can go to my website. Just look up the plant disease diagnostics clinic at the University of Wisconsin-Madison and you should be able to find it us very, very easily. We have information on how to submit a sample. We also have a lot of fact sheets. I also do a weekly summary of the diseases that I have seen in the clinic which is called Wisconsin Disease Almanac and there’s a tab for that on the website as well.

Sevie Kenyon – We’ve been visiting with Brian Hudelson, plant diagnostic lab, University of Wisconsin-Extension Madison in the College of Agricultural and Life Sciences and I’m Sevie Kenyon.