Claysburg, Pennsylvania. Claysburg is a census-designated place (CDP) along Interstate 99 and the Allegheny Front near the base of Blue Knob (Pennsylvania). As of 2010 census, it had a population of 1,625. As of the census of 2000, there were 1,503 people, 616 households, and 442 families residing in the CDP.
Total U.S. corn production was 13.9 billion bushels in 2013, 10.8 billion bushels in the drought year of 2012, and 12.3 billion bushels in 2011. The 2015 average U.S. corn yield is now estimated at 168.0 bushels per acre, which is a slight increase from the September estimate of 167.5 bushels per acre. The 2014 projected national average corn yield compares to the record U.S. corn yield of 171 bushels per acre in 2014, 158.8 bushels per acre in 2013, 123.4 bushels per acre in 2012, and 147.2 bushels per acre in 2011.
In any case, crop yields for barley tend to range between 5 and 40 bushels per acre. Here in Colorado, that number is typically around 25 bushels/acre. Converting this to pounds per square foot isn't exact - a bushel is a unit of volume. Healthy barley will be more dense than unhealthy barley, but farmers shoot for 48 pounds per bushel in barley harvests. Using that figure, you'd be looking at .027 pounds per square foot.