13 reactions | Island Chlorosis on Hackberry is disease that’s not very well known. What is known is that is causes yellow (or chlorotic) blotches on leaves. These blotches can be separated from each other making them look similar to islands, hence the name. If you see these symptoms on your Hackberry tree - no fear! The symptoms of this disease are aesthetic and your tree may still be healthy. | Texas Plant Disease Diagnostic Lab | Facebook