On Ebay I have ordered a set of 1/64 scale model pivots.
On the box it says:
Pivot irrigation allows farmers around the world to grow more food using less resources. In 1954, Robert B. Daugherty, founder of Valley Manufacturing Co., acquired patented manufacturing and sales rights for a self-propelled irrigation system from farmer Frank Zybach. Since then, Valmont has grown to become the largest manufacturer of center pivots in the world, irrigating about 17 million acres (6,9 million hectares)
With this scale model pivot I will try to grow one square meter of cress in my studio.