Hi Andrea,

I think you may have spider mites. They are very tiny insects that suck out the juices in plants and leave them looking stippled .

https://extension.umn.edu/yard-and-garden-insects/spider-mites

Out hot dry weather is what they thrive in. Spray your tree canopy every day with the hose and that might help. Our new weather patterns are allowing a lot more pests and disease to thrive unfortunetly.

Sally Granath

MG St> Louis County

Hello.

I do agree that there are likely some spider mites eating the Redbud leaves. 
Yet I suspect that there is another very small insect at work.

These have wings. 
If you would please see the attached photo?

Not sure if the photo quality is good enough. I placed a redbud leaf upside down between two glass pie plates. And I wrote numbers 1-6 in blue where I see the winged insects. 

Maybe these are whiteflies? 
thank you!

Wow,

You sure have problems with that tree. I found another link for you to look at :

https://byf.unl.edu/e2cc2f52-c8fe-4252-9332-fec7215afb04.pdf

Two spotted spider might ?

I think your tree is so weekend it now has several insects feeding off it. It can't hurt to spray it with an insecticidal soap.

I would definitely spray the tree this fall with horticulture oil and again before bud break in the spring. Make sure the tree gets watered once a week.

Sally Granath

St. Louis County MG

Hi Andrea, 

I think you are right. I'm thinking they are leaf hoppers.

https://ipm.ucanr.edu/PMG/GARDEN/VEGES/PESTS/leafhopper.html

Make sure the tree gets watered once a week ( 5 gallons or so). The tree is stressed in this hot dry weather. It can't hurt to spray your tree with a strong blast from your hose and try and knock the bugs off (if that is doable). I've gotten many inquiries about the same issues with red bud trees. They are clearly more stressed and thus, more vulnerable to insects.

Both insects are soft bodied so you can try insecticidal soap and horticultural oils.

There is a lot of research out there and I encourage you to look at what has been found effective. If you can keep your tree watered that will help. Often they can withstand insects .

Hope this is helpful,

Sally Granath

St. Louis County MG