The ornamental design for a treedraingrate, as shown and described.
FIG. 1 is a top perspective view of a tree drain grate showing the new design;
FIG. 2 is a top plan view thereof, the bottom plan view thereof being a mirror image of FIG. 2;
FIG. 3 is a right side elevational view thereof, the left side elevational view thereof being a mirror image of FIG. 3; and,
FIG. 4 is a side elevational view thereof taken from the bottom of FIG. 1, the side elevational view from the top of FIG. 1 being a mirror image of FIG. 4.