Crepe Myrtle leaves shriveled

Question: The leaves on the ends of the branches of my very large crepe myrtle are shriveled and white instead of green. Is this a fungus or caused by insects? I have also seen a few black ants on the trunk. This tree is located in a large flower bed where drainage is good. 
I don’t know what product to use or how to treat this tree because it is so tall. Can you advise?

responder: An Ask Extension Expert Replied May 15, 2023, 10:34 AM EDT
response: Thank you for your question. Unfortunately, the photos you sent are very blurry and compressed and I would not feel comfortable making a diagnosis from those. Could you send better photos of a close up of the leaves, the trunk of the tree, and the entire tree? Also do you notice any browning/darkening of the bark/trunk itself?

responder: The Question Asker Replied May 15, 2023, 11:42 AM EDT
response: The photos I sent in my original email had to be downsized in order for them to be able to send, and I think that compressed or changed the files. I am going to send a couple of photos at a time in a couple of emails in their regular size, hoping they won’t be blurry or changed. Sent from my iPhone On May 15, 2023, at 9:34 AM, Ask Extension <<personal data hidden>> wrote:﻿

responder: The Question Asker Replied May 15, 2023, 11:48 AM EDT
response: These are additional photos of my Crepe Myrtle. Sent from my iPhone On May 15, 2023, at 9:34 AM, Ask Extension <<personal data hidden>> wrote:﻿

responder: The Question Asker Replied May 15, 2023, 11:58 AM EDT
response: I just got on a ladder and cut these limb ends so I could get these up-close photos of the leaves. Sent from my iPhone On May 15, 2023, at 9:34 AM, Ask Extension <<personal data hidden>> wrote:﻿

responder: An Ask Extension Expert Replied May 15, 2023, 12:31 PM EDT
response: Are the white leaves only on new growth or is it on the older leaves from the tree as well?

responder: The Question Asker Replied May 15, 2023, 1:31 PM EDT
response: It is only on the new leaves on the ends of the limbs. Sent from my iPhone On May 15, 2023, at 11:31 AM, Ask Extension <<personal data hidden>> wrote:﻿

responder: An Ask Extension Expert Replied May 15, 2023, 2:51 PM EDT
response: I believe what you have is a powdery mildew fungus.  Powdery mildew grows best on young, actively growing plant tissue. They may cover new plant growth entirely and cause severe damage to these parts. Older leaves are less likely to be affected. In addition, powdery mildew can cause infected shoots to dry up and shrivel and cause infected leaves to grow abnormally (curl and twist).  The best management method is prevention. Use resistant varieties of crepe myrtle, provide the plants with full sun, and use good cultural practices, such as avoiding excess fertilization and removing affected leaves in the fall, will adequately manage powdery mildew in most situations. Once these sprouts become infected, the fungus easily spreads to the upper portions of the plant. Encourage good circulation through selective pruning and/or proper placement of the plant in the landscape to reduce chances of spore settling and humidity level, and allows for full sun. Crape myrtle varieties with excellent resistance to powdery mildew include Tonto, Muskogee, Acoma, Souix, Tuskegee and many others. There are numerous fungicides, both natural and synthetic, that are available to control powdery mildew. Care should be observed when using any fungicide, and effective reading of the label for application directions. Natural fungicides such as Neem oil extract and Potassium bicarbonate has been shown to be effective when used correctly. Fungicides are typically not needed at the hottest part of the year (and not recommended at temperatures above 85 degrees) as the powdery mildew fungus is inactive and the fungicides may cause damage to the plants.  Attached are a couple extension articles I found of Powdery Mildew on Crape Myrtles: https://plantclinic.tamu.edu/factsheets/powdery-mildewappears-on-crape-myrtles-this-factsheet-tries-to-explains-the-disease-call-powdery-mildew-an/ https://hgic.clemson.edu/factsheet/crape-myrtle-diseases-insect-pests/ http://extension.msstate.edu/publications/information-sheets/the-plant-doctor-powdery-mildew-crapemyrtles