Answer: Based on your description it sounds as though the tree may not have rooted into the surrounding soil very well. This can happen if the tree is planted in a small, smooth sided hole in heavy clay soil, if there are encircling roots not cut or unwound at planting, if the tree is planted too deeply, if the tree is watered incorrectly or planted in a very dry or very wet location, and so on. Or, it is possible there is damage to the graft or trunk. These trees are grafted, so if the top portion of the tree fails to thrive then the rootstock may send up suckers to try to overwhelm the grafted top. I would suggest you consult with your local county extension and/or the retailer where you purchased the tree for help in troubleshooting. I'm sorry I can't be more specific for you long distance.
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