Q.Natchez crepe myrtle’s leaves are wilting
My large Natchez crepe myrtle’s leaves are wilting and the limbs are covered with spider webs. The suckers at the base of the crepe myrtle are healthy and blooming. The crepe myrtle is large and has no blooms.
This could be an infestation of spider mites or even tent worms.
A heavy infestation of spider mites can weaken a Crepe Myrtle.
Neem Oil is a good treatment, and I would use weekly to kill the insects and can be used throughout the growing season.
https://www.gardeningknowhow.com/ornamental/trees/crepe-myrtle/crepe-myrtle-tree-problems.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
https://www.gardeningknowhow.com/plant-problems/pests/insects/tent-worms-control.htm