Plant and Insect Diagnostic Clinic Dos and Don'ts

We’re well into the growing season in Iowa. We are in full swing in the Plant & Insect Diagnostic Clinic (PIDC) as Iowans begin noticing different plant or insect issues in their home, yard, and garden. While we have information on our PIDC webpage about services that we provide, with some sample snafus this spring, we figured it was time to write a brief newsletter article to remind you here, too.

At the PIDC, we accept several different sample types: plants, insects, and soil. But what can we actually do with every kind of sample, and what can’t we do? Let me lay it out for you.

Tree with stem girdling roots. Without photos sent along with samples, we never get the whole picture of all of the factors that are affecting the plant’s health. 

Plant Samples

DO send us plants for plant problem diagnoses.

DON’T send us plants for A) plant identification or B) herbicide residual testing. 

  • A) If you want to get a plant identified, we recommend contacting your county office for help, as they have several resources at their fingertips that they can use to help! For more on finding your local office, see this link.
  • B) If you’re concerned about herbicide drift damage in your garden, you can read this previous HHPN article. Here is a list of laboratories that can test for herbicide residuals on plants. If you plan on sending a sample to one of the labs listed, we advise you reach out to them before submitting a sample to ensure you send all the necessary information and the right kind of sample. 

DO fill out our sample submission form in its entirety (there are two pages!) and be as thorough as possible when describing the problem.

DON’T send money with your sample submission form. You will be billed by the University after services are complete and you get your sample report.

DO send us photos to go along with your plant problem submissions. As they say, a photo can say 1,000 words and are very helpful in understanding the problem in the environment.

DON’T use our PIDC text line to send us photos of plants or plant problems without talking to us first via email ( or phone (515-294-0581). However, photos can be sent to us via email without first talking to us.

DO consult sample preparation, packaging, and shipping guidelines on our website before sending a sample. Sample submission instructions vary by the type of plant you are sending!

DON’T send a sample on a Friday, as we don’t want samples sitting in hot mail trucks over the weekend. If you send a sample on a Thursday, we recommend overnight shipping it. Any questions about mailing samples, please don’t hesitate to ask us!

Rose aphids parasitizing a rose plant.  


DO send us insect/arthropod samples from your home, yard, and garden.

DON’T send us insect/arthropod samples that include any animal/human materials (e.g. blood, skin, hair).

DO use the PIDC text line or PIDC email ( to send us photos of insects or arthropods for identification. Photo identification comes at no charge. However, sometimes identification cannot be made via photo alone and we’ll ask you to send a physical sample, which costs $10. In some cases, molecular insect identification may be warranted. If so, we’ll talk with you to see if you’re okay with the additional costs.

DON’T ask us to run tests for tickborne pathogens that come with tick ID requests. This is not a service we provide.


DO send us soil from your yard only if you want us to quantify the plant parasitic nematodes that could be harming your turf.

DON’T send us soil to test for other plant pathogens. This is not a service we provide.


DO get yourself a copy of the “Safe Mushroom Foraging” book from the ISU Extension Store! The PDF is free and the book itself currently costs just $4.00.

DON’T ask us to identify mushrooms for you. This service was discontinued some time ago due to liability issues.

DO consider attending one of our wild-harvested mushroom workshops in the spring if you want to increase your confidence at identifying mushrooms for yourself.

PIDC reports

DO expect to get management recommendations (where applicable) once we are done with your sample in the PIDC. The report provides information about the diagnosis (pathogens or insects found, suspected environmental stresses), and we research and share management recommendations, where applicable, to mitigate the problem.

DON’T hesitate to reach out to us with any questions you have!

We strive to be a top-notch diagnostic laboratory. If you have any questions or concerns, please do not hesitate to reach out to us directly at

Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Yard and Garden, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on June 6, 2023. The information contained within may not be the most current and accurate depending on when it is accessed.