Thread by @ScottIrwinUI

1. While waiting for today's Crop Progress report want to share highlights from a #FDD that TH and I wrote last week on corn planting speed. Previous work was limited to the 3 I-states. This one uses all the available data 18 states. farmdocdaily.illinois.edu/2020/04/furthe…

2. The key claim that seems to be nearly universally believed is that we can plant corn faster in the US now than in the past. Data here is for 17 states representing almost 90% of US corn planted acreage (Texas left out since it only started with suitable field days in 2014).

3. Since 1995, there is no evidence across the Corn Belt that in our best weeks we can plant more acres per suitable field day. In fact a slight decline. But average for maximum rates of progress looks pretty flat at about 4.5 million acres per suitable field day.

4. Situation is even more surprising if we put the maximum rate on a % basis. A notable decline in the maximum % corn planting progress per suitable field day. What gives?

5. The reason for the decline in maximum % planting progress per suitable field day is as follows: over 1995-2019 US increased corn planting by 22 million acres. With stable maximum rate of 4.5 million acres per day, the % planted per day must necessarily drop.

6. Here is where things get really interesting. We did not find this result (declining maximum %/day) in the three I-states. This means that we expanded corn production into areas that plant at a slower rate than in the heart of the corn belt. I want to dig into this more.

7. For the same reason, the minimum # of suitable field days to plant the 17 states has increased since 1995. From about 14 to 19 suitable field days planting at the maximum rate per day.

8. So can we put to bed the myth that we can plant the entire Corn Belt in 5 days? Planting flat out the entire time (not realistic), today it takes about 3 weeks. That is a far cry from a week or less.