Plant Disease and Insect Diagnostic Laboratory-Oklahoma State University

05/26/2026

What's wrong with this tomato plant? Damage from Thrips.

05/24/2026

05/22/2026

Slime mold! The first picture (yellow clumpy) is when the slime mold was younger and starting to aggregate. The second image is 48 hours later with the brownish ball. Check out this link for more information. https://www.youtube.com/watch?v=bH6q7iUKfQ4

05/20/2026

Check out these pear rust lesions. They will be releasing spores soon that infect Eastern red cedar (junipers). For info about pear rust, see this link: https://extension.okstate.edu/fact-sheets/pear-rust

05/19/2026

This kohlrabi has holes, but it's not due to caterpillars. It's earwig damage!

05/17/2026

We've received several fire blight samples in the past week. Check your apples and pears!

05/16/2026

Sara Wallace and Nicole Baker representing our lab today. Please contact your county extension office or us if you have plant disease or insect problems in wheat or other crops.

Plant Disease and Insect Diagnostic Lab promoting their services at the Lahoma Field Day. Big shout out to Sara and Nicole for promoting the lab and department.

05/15/2026

This leaf cutter bee cut a circle (like a hole punch) from this Mandevilla flower petal to build her nest.

05/13/2026

If American elms in your area are suddenly wilting, it might be Dutch elm disease. We have received 3 samples of this disease in the last 5 days. Note the streaking in the xylem where we peeled the bark. To confirm the disease, we remove wood chips from the streaky area and place them on agar media. In 5-7 days, the fungus produces sticky spore structures called synnemata (singular=synnema) which you can see in the images.

05/12/2026

They're back! These are vine borer eggs and I also squashed a squash bug adult.

05/10/2026

If your plants experienced hail, remove severely damaged foliage. Remove broken branches and make clean cuts. Wait to fertilize until new growth appears. Keep plants irrigated during periods of drought. Be patient. It is best to wait a few days to weeks to fully assess damage.