Thread by @ScottIrwinUI

1. Hot off the press. TH and I have a new #FDD on one of my personal favorite topics: how fast can we plant the corn crop. Something everyone in ag has an opinion about. farmdocdaily.illinois.edu/2020/04/an-upd…

2. We have to be able to plant the Corn Belt faster now than in the past with all those huge planters, right? Wrong. This shows number of corn acres planted in Illinois per suitable field day during two peak weeks of planting progress. Virtually no trend back to 1980.

3. Same thing for Indiana

4. Iowa data a little funkier, but same overall message. Little if any evidence that we can cover more acres planting per suitable field day in 2020 than we could in 1980.

5. A key implication is that it takes a minimum of 14 suitable field days to plant the US corn crop. Note that is the minimum. Usual variation in weather and field conditions means that it typically takes more days.

6. I am sure I will get a lot of blowback on this article and the findings. People see the huge planters and it is natural to think we have to be able to plant the crop faster than in the past. But they forget that the big planters have to cover a lot more acres.

7. Key insight: bigger but fewer planters today plant about the same acres per day in aggregate as more numerous but smaller planters did in the past

8. Certainly some farm operations have the capacity to plant their total corn acreage faster than in the past. That has to be true. The fallacy is to apply that logic to all farm operations and argue it is true in the aggregate.

9. Remember I am talking about large scale planting progress, say for a state or the Corn Belt as a whole. The data show that increased planting speed does not hold at that scale.

10. Lastly, we can use the 14 suitable field day rule of thumb to help us assess in real time whether COVID-19 is slowing down the corn planting supply chain. If bulk of US corn crop is not planted after widespread 15-20 suitable field days, Houston we have a problem.