This bread (well, bread-to-be) came from a plot of about 2,000 acres. The paddock was about 3,000 acres, but not all was cleared for farming, the lesser quality soils weren't bothered with - example the part in the photo.
Dumping wheat on the ground is far from ideal. It was not common practice. However it has to be harvested when it is ready, there was only 200 tonnes of on-farm storage, and there is a time frame in which to deliver it. The depot closes on a certain date, and that is "it" for deliveries for that season.
I forget the yield. I kept a ledger of every truck that loaded, there was about 3,000 tonnes handled this way. It went about 17% protein, which is about par on that country.