The Crepe Myrtle (Lagerstroemia indica) is a beloved ornamental tree known for its extended summer bloom. However, its leafless, seemingly lifeless state in late winter and early spring often causes concern, leading homeowners to wonder if it has succumbed to cold or environmental stress. Determining the true health of a Crepe Myrtle requires a systematic approach to distinguish between natural dormancy and actual death. This assessment is crucial before deciding on removal or extensive pruning.
The Definitive Scratch Test
The most reliable method for assessing the viability of a Crepe Myrtle is the scratch test, which checks for living tissue just beneath the outer bark layer. Use a clean fingernail, knife, or pruner edge to gently scrape a tiny patch of bark, starting with smaller branches, as these are the first to show dieback. A healthy, living branch will reveal a moist, bright green layer immediately beneath the outer bark, indicating active tissue. If the scraped area is dry, brown, or gray, the tissue is dead; if the test moves to the main trunk near the soil line and also tests brown and dry, the tree is likely dead to the ground.
Visual Signs of Distress or Death
Beyond the scratch test, several visual and tactile indicators can confirm the tree’s condition. A living branch should be flexible, bending slightly without breaking, while a dead branch will be dry and brittle, snapping easily like a twig. Look for areas of abnormal discoloration on the bark, such as uniform blackening, which may signal sooty mold associated with Crepe Myrtle Bark Scale (CMBS). Heavy infestations of CMBS can cause branch dieback and stress the plant. Also inspect the trunk for signs of advanced decay, such as soft, hollow areas or a noticeable foul odor.
Distinguishing Dormancy from Death
The greatest source of confusion is the Crepe Myrtle’s tendency to be one of the last trees to break dormancy in the spring. In many regions, they may not begin to show signs of leafing out until late May or early to mid-June, which is a natural characteristic, especially following a cooler winter. A true winter kill, often experienced in colder hardiness zones, usually means the above-ground growth has died, but the root system remains viable. This phenomenon is called “dieback,” and the tree will often push new shoots, known as suckers, from the base or roots. If the upper branches test dead, but you see shoots emerging from the soil line, the roots are alive, and the tree is merely regenerating. It is wise to wait until late June before declaring a Crepe Myrtle completely dead, as the root system is remarkably hardy.
Action Steps Based on the Diagnosis
Once the extent of the damage is determined, appropriate management steps can be taken. If the scratch test reveals only the upper branches are dead, the best course of action is selective pruning. Use sharp, clean tools to cut the dead wood back to a point where live, green tissue is found, making the cut just above a healthy bud or branch junction to encourage new growth. If the roots are alive and sending up new shoots, manage the new growth by selecting a few strong shoots to become the new trunks. If the tree is confirmed to be fully dead—no green tissue or suckers by late June—it should be removed, including the root ball, to prevent attracting pests and diseases.