The ornamental design for a Christmas Tree Elevation Stand, as shown and described.
FIG. 1 is a front perspective view of my Christmas tree elevation stand; the rear view being a mirror image
FIG. 2 is a top plain view of my Christmas tree elevation stand; and,
FIG. 3 is a right side view of my invention; the left side view being a mirror image; the Christmas tree elevation stand includes a flat and unornamented bottom which is not shown.