Certified GKH Gardening Expert
Thank you for sending us your gardening question. You did not specify whether it was the branches or the center of your tree turning brown. If it is the lower branches turning brown, it could be cytospora canker. If it is browning from the inside, it could be mites, in which case you should apply a miticide.
As for the burlap and wire, natural burlap will disintegrate in the soil. Baskets made from heavy gauge wire are often used to help hold a B&B root ball intact during shipping and handling. Wire also allows for the tree to be picked up by the root ball instead of the trunk. This is a very effective means of ensuring that roots inside the root ball remain intact with soil. Wire in baskets degrades slowly in soil, and can be intact 20 years after planting. However the welds typically degrade sooner. There is no research documenting the detrimental effects of wire baskets on trees. In fact, some research shows that roots engulf the wire with little apparent harm to the tree.
Here are a couple of articles you might find helpful:
Please let us know if you have any other gardening questions and happy gardening!
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