Thanks for your question. It is posing a challenge to me. Please do me a favor. Closely look over your Solidago rigida (both sides of the leaves, stems, etc). Do you see anything that looks like the attached picture?

In your examination of the plant, do you observe any very small insects that seem to

”jump” from the plant?

For the pictures that you included in your question, can you give me a specific date at which they were taken?

Looking forward to your response. Many thanks.

Thanks for the response! I have not seen any of those leafhoppers, but I'll check the plant today to confirm. The insects in my photos don't move much. Some of the bigger ones I've found (no bigger than 1/8 in) were crawling on their own on the plant, but most were gathered on the underside of a leaf. I've attached another photo of the group. All photos were taken Saturday, 9/13/2025.

Thanks for your recent picture.  I'm pretty sure these are planthopper nymphs in the Flatidae family or a related family in various late instar nymph stages .   Given the lateness of the season, I'm would not expect to find any adult planthoppers.  I've largely ruled out Orthezia urticae as a possibility.  I have a consult coming up later this morning with an entomology colleague regarding my thoughts.  I expect to have a final answer to you later this morning.  In the interim, I would appreciate receiving any additional thoughts you might have.

Many thanks.

Thank you for your patience in our attempts to fashion an answer to your question. I believe that I can now do that with a reasonable but not absolute certainty. In so doing I consulted with an entomology colleague, looked at numerous peer reviewed articles, and closely examined under high magnification the excellent photographs you provided.

I am ruling out Orthezia urticae and any members of this genus as possibilities for the following reasons:

1). Orthezia urticae is a scale insect. Immature forms (“crawlers”) are very small and can only be seen for short periods of time. Your image 20250913_160159.jpg is presumably portraying immature forms of whatever is on the Solidago rigida. These immature forms are clearly larger than crawlers and these forms differ in size. Different sized immature forms (nymph instars) are consistent with a gradual metamorphosis. Scale insects do not have a gradual metamorphosis.

2). As you correctly pointed out in your original question, Orthezia urticae has not been reported in Minnesota. In fact, there are only scattered reports of it being found in North America.

3). In the published literature, there are no reports that Orthezia species feed upon Solidago plants.

4). Although there is some resemblance between images of Orthezia urticae and what is on your Solidago, I don’t feel that there is anything approaching a good match.

I am of the mind that your pictures are showing Solidago planthopper nymphs in various instar forms. I am unable to ascertain the genus or species of planthopper. The nymphs and adults feed upon plant juices and generally cause little if any damage to the plant. They produce a liquid called honey dew that can attract ants and various pollinators. If you have seen ants and/or wasps on the Solidago, that would be additional evidence that planthoppers are present. See the following for general information about planthoppers (note the statements that nymphs can be covered with a waxy substance):

https://www.gardeningknowhow.com/plant-problems/pests/insects/planthopper-insect-pests.htm

https://mdc.mo.gov/discover-nature/field-guide/planthoppers

https://edis.ifas.ufl.edu/publication/UW525

My additional thoughts are:

1). These planthoppers are common in Minnesota on Solidago and related plants. More specifically, I’m reasonably confident that they are flatid planthoppers reflective of the fact that they are in the Flatidae family. See:

https://extension.msstate.edu/newsletters/bugs-eye-view/2015/flatid-planthoppers-no-11

https://www.michigannatureguy.com/blog/2013/09/03/planthoppers/ - :~:text=The first one is in,bright yellow or orange eye.

2). Here are some images of Flatid planthoppers nymphs and adults:

https://bygl.osu.edu/node/348

https://bugguide.net/node/view/429637

3). I used AI to do an extensive literature search for Flatid planthopper nymphs. For what it’s worth (remember it’s AI), I am attaching images of different nymph instars of planthoppers that were found in examined web sites.

4). These planthoppers do not overwinter in Minnesota. For this reason, you may or may not see them in 2026. They migrate to Minnesota from more southern states.

5). The nymphs in your picture have layers of plates on their dorsal sides with a heavy wax layer. Under these plates are folded filaments that can be extended out from the nymph. This is why you will sometimes see nymph images showing these filaments.

That’s about the best I can do. As I said, I still have some lingering doubts about my identification. Thanks for consulting our forum

Thank you so much for this great response! I'm relieved to hear that it isn't Orthezia urticae and it was interesting to learn that planthopper nymphs can produce that waxy covering.

A researcher on iNat from UMass also suggested it could be Orthezia solidaginis, which does have several observations in the state.  I think that species is native, though,  so that would be good news, as well. I guess I'll know more next year - if they don't make it through the winter, then likely planthopper, as you said! 

Again, thanks for your thorough response - I appreciate all of the work that went into it! 

Thanks for your last note.  I looked at Orthezia solidaginis and consider that to be a strong second possibility.  It is a scale insect.  If one wanted complete closure, then it would require determination of whether or not the insect visiting you is scale.  To accomplish that one could not depend upon just photographs.  There are various anatomical features that would need to be examined under a microscope.  I think that you raised a good point.  If you don't see these critters in 2026, then it would make the case that planthoppers are involved.  If they appear in 2026, that would be consistent with their being scale.

It has been a pleasure interacting with you about this question.  Thanks again for consulting us.