Here's what the Yardener suggests. If you have a large tree or a number of trees I recommend you have a certified arborist do an on-site inspection. Professionals have high powered sprayers and the ability to reach branches at the top of the trees. To find a qualified tree care company call 800-733-2622 or go online at www.tcia.org. Best Nancy and Thanks for visiting Yardener.com.
*Leaves Near Stem Tips Turn Brown shows Tip Blight* A tip blight caused by a fungus sometimes attacks crape myrtles. Leaves near the branch tips turn brown in late spring or early summer. Tiny black spore-bearing bodies appear on infected leaves. Spray plants with copper fungicide or lime sulfur fungicide when symptoms first appear and then every 10 days in wet seasons. Avoid overhead watering which keeps foliage moist and fosters the disease. Prune to increase air circulation around plants, taking care to sterilize pruning tools by dipping them in household bleach to avoid spreading the disease. Because the fungus spores collect on the mulch beneath the shrubs, removing the old mulch and replacing it with fresh material may help prevent an outbreak from recurring. If this blight is a common problem every year, prune and destroy affected plant parts in the early spring. Spray a copper fungicide or lime sulfur in four applications: (1) after the dead leaves and dying branches have been removed and before growth starts in the spring; (2) when growth is half completed; (3) after spring growth has been completed; and (4) after fall growth stops. Take care to determine if the crape myrtle twigs are turning brown from frost damage rather than disease. For more information see file on Controlling Fungal Disease