Silver maples are naturally shallow-rooted, especially in a compacted clay soil where there is not much pore space (oxygen) available, forcing roots to grow very near the soil surface. As these expand in diameter, much like the trunk and branches do, it will appear as if roots are "coming up." This root expansion is often the cause for sidewalk lifting by tree roots.
Removing one large flare root (there are probably six to nine major flare roots) will likely result in some dieback of 1/9 to 1/6th of the top of the tree. You may notice that some branches do not leaf out in the spring as a result of root removal. Some twigs/leaves may die back as soon as hot weather arrives. If you removed more than one major root, more dieback is likely and stability in winds becomes a possible issue.
Will the tree survive? Yes, if the tree is in good health and only one to two major flare roots were removed, but with some likely dieback in the top. Note that regrowth of roots from the cut root stub(s) may be rapid.
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horticulture, ornamental trees, root removal