Good Morning,
Because redbud leaffolders fasten the leaves together tightly, it may be best to use a systemic pesticide such as Orthene should control be necessary. Whatever pesticide is used should be sprayed on thoroughly to try to get in to soak into the shelters where the leaffolders are feeding. Another control strategy would be to apply a systemic insecticide such as imidacloprid to the soil under the tree in late winter. That would give the tree time to translocate the active ingredient up to the forming leaves. Both Orthene and imidacloprid are available in big box stores and garden centers. Imidacloprid is a Bayer product available in several formulations. Look for the active ingredient listed on the front of the package usually in very small font.

Redbud Leaffolder | Oklahoma State University (okstate.edu)
Redbud Leaffolder | NC State Extension Publications (ncsu.edu)

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