We claim the ornamental design for a reel mower, as shown and described.
FIG. 1 is a top perspective view of a reel mower showing our new design;
FIG. 2 is a front elevation view of the claimed design;
FIG. 3 is a back elevation view of the claimed design;
FIG. 4 is a right side elevation view of the claimed design;
FIG. 5 is a left side elevation view of the claimed design;
FIG. 6 is a top view of the claimed design; and,
FIG. 7 is a bottom view of the claimed design.
The ornamental design which is claimed is shown in solid lines in the drawings. The broken lines in the drawings are for illustrative purposes only and form no part of the claimed design.