At the time he submitted his proposal Mr. Woodward grew shiitake mushrooms. His procedure for growing the mushrooms involved drilling holes in logs of red oak, filling these with shiitake inoculum, then leaving them to sit for a year. Thereafter the logs were immersed in water to promote fruiting, picked, and immersed again repeatedly; this meant that they had to be moved a lot.
To reduce the amount of handling, Mr. Woodward built a cage to hold the logs. He made it of angle-iron. He built it to hold 24 logs, each log in its own open compartment, sufficiently confined that it would not float away when the whole structure was immersed, but sufficiently open that he could reach each with a knife to cut the mushrooms off, without first having to remove it.
He attached a chain to the top of the cage, so that he could move it around with a front-end loader. Because of the buoyancy of the logs the structure, when loaded, would not sink, but he worked out a method of pressing down on the cage with the bucket of the front-end loader, then using C-clamps to anchor the cage in the immersion tank.
Shortly after completing the structure Mr. Woodward quit growing mushrooms, simply because he found raising organic chickens to be more lucrative. He says the structure worked well though, and that it definitely helped save labor.