Comments from the Early Rail Group:
The Monterey & Salinas Valley was built to move grain to port. When operating, sporadically from 1874 to 1880, it used every car it had in the annual fall grain rush—40 flats and 8 boxcars—to move thousands of sacks from shipping points (often just sacks stacked by the track) to the main warehouse at Monterey before the rains came. Using flats was a weakness, uncovered sacks on the cars did get wet and spoiled.
In California during the nineteenth century, sacks of grain were regularly shipped on flat cars.