Answer: Unfortunately, based on your description it is impossible to determine the cause of the browning. Keep in mind that dogwoods need an evenly moist but not soggy soil so be sure you are not overwatering it. A few inches of mulch over the root zone (but not touching the trunk) can be helpful in keeping the soil cool and moist. It is possible that your trees came from different sources originally and thus the composition of the rootballs are different so that they may respond differently to watering. You will need to dig down a bit and see to know for sure if and when and how much to water. The soil in your area may be naturally acidic enough already, and it may or may not be necssary to fertilize the trees. ( In general it is not a good idea to fertilize a stressed tree.) The only way to know for sure is to test the soil. Your county extension can help you with the tests and interpreting the results. They should also be able to help diagnose the foliage problem. You might want to give them a call at 745-3445.
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