Apparatus for excavating ballast from adjacent to the ends of and beneath the cross ties of a railroad bed and for cleaning the excavated ballast for return thereof to the railroad bed. The apparatus includes a vehicle for supporting a pair of excavating assemblies on opposite sides of the vehicle. Each excavating assembly includes a pair of spaced excavating wheels for excavating ballast from adjacent to the opposite sides of the cross ties and an undercutter for excavating ballast from beneath the cross ties at opposite ends thereof. A discrete cleaning station is provided for each excavating wheel to receive and clean the ballast picked up by each excavating wheel. Means are provided for conveying and discharging the cleaned ballast back onto the railroad bed.