Answer: Browning at the top is not a good sign. With a new plant it often indicates lack of soil moisture, poor planting technique, or poor rooting. It could also be a sign of an insect or disease problem. I would suggest you consult with your local Cornell extension to try to determine the cause of the browning.
In the meantime, make sure the tree is mulched with several inches of organic mulch over the root area; it should be applied in a flat layer surrounding the tree and should not touch the trunk or bark of the tree.
Also be sure you are watering correctly, as needed to supplement rain. Your goal in watering is to keep the soil evenly moist like a wrung out sponge, not sopping wet and not dried out. To know if you need to water, dig into the soil with your finger. If it is still damp, do not water yet. When you do water, apply it to the soil surface and water thoroughly and slowly so it soaks down to the deeper roots. After watering, wait a few hours and then dig down to see how far the water soaked in; it can be surprising.
There is no set schedule for watering, it depends on your soil type and on the weather. Using an organic mulch several inches thick over the root area will help reduce watering needs as well as feed the soil gradually as it breaks down over time.
If there is a warranty on the tree, you may also want to check with your retail store, landscaper and/or installer.
Good luck with your tree.
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