Planted 20 , 2-3" diam. Zelkovas on same well-drained landscape position 3 yr. ago. Drip irrigation installed then. About 4" now and 15 ft. tall. All were vigorous and healthy until ~ 2 wk. ago when one in middle of row developed grayish bark and all leaves quickly curled and turned brown. Foliage gone and bark abnormal. Appears dead. What may be cause. Can bring bark and leaf sample is helps. Can also email photo.
New Castle County Delaware
Please bring branch, bark and leaf samples for diagnosis. And here are a few questions to answer as well. Did Zelkovia replace diseased trees/shrubs in the same place? Do you see any symptoms on adjacent trees? Is there mulch piled up at the base of the trees? Can you see any circling roots at the base of the tree? Have the trees been watered regularly since they were planted? Pictures of the tree and ground around it would be helpful.
Fill out the diagnostic form at http://extension.udel.edu/ag/plant-diseases/ud-plant-diagnostic-clinic/how-to-submit-a-sample/ and bring it, pictures, the samples in plastic bags to the New Castle County Cooperative Extension Building at 461 Wyoming Road in Newark. Enter the door under the red canopy and go straight down the hall to the kiosk on the right. Leave everything on the self below the writing surface. Someone will call you with a diagnosis in about a week.