FWIW, out of the 90+ trees that we transplanted last month with a tree spade, one tree was tipped over by the wind the next day after transplanting. It was a VERY nice looking White Oak Tree. Very symmetrical crown, close to 20' tall, about 5"-6" DBH. It was transplanted from an area that had a high water table, and the roots didn't grow very much. The roots were maybe 1/10th the size of the crown of the tree, and weren't enough to act as an anchor for the tree.

I think the only reason why it didn't uproot in the area that it was growing was because there were other trees the same size growing in close proximity, helping protect it from the wind. Once it was transplanted, it didn't have that protection and over it went.

The tree spade was a large one, taking a plug that was approximately 5' in diameter, and 5' deep.

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