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1. Good morning. Its crop progress AND crop condition Monday for corn and soybeans. Let's talk corn planting progress first. Here is the 7-day precip map for the US. 
2. Better looking map than previous week but still enough precip around to slow or stop planting in many areas. Best places look to be eastern SD, SW half of IA and central IL.
3. So, I am guessing that 50% of Corn Belt had 5-6 suitable field days and 50% had 1-2 suitable field days. That averages out to 3.5 suitable field days for the entire Corn Belt.
4. Really hard part to guess under these conditions is the planting progress per suitable field day. I am going to use 4% progress per day. 4% per day X 3.5 days = 14% total corn planting progress. 67% +14%= 81%.
5. I am going to add 1 point for PP upward drift in the USDA reported planting progress to hit 82% as of June 9th. See the market is at 80-85%. Anything in that range seems reasonable to me.
6. Let's use 85% planting progress this week to be a bit conservative. That implies 14 million acres of corn still unplanted as of June 9th. Here is where things really get interesting to me and I seem to have a very much minority view about what should happen next.
7. Market seems to think that corn planters are just going to keep rolling from June 10 forward to get those 14 million acres planted. What I know is that he field trial data imply a massive hit to expected corn yields for planting at this extremely late date.
8. Thought I would throw this out there today to try to explain why planting corn in June is not expected to work out very well. Chart is from a study by Ken Cassman at Univ. of Nebraska.
9. Chart shows relationship of corn yield to sunshine (solar radiation) absorbed during grain fill. Critical for corn yield. More total sunshine = more corn yield. Sunshine per day is pretty constant, so key is the number of total days during the grain fill period.
10. When you plant 30-45 days late as we have in many areas this year you are more than likely chopping of a big chunk of the grain fill period. Hence, the large expected decline in corn yield for planting in June. Not really that complicated.
11. Should have said that I am a big fan of Ken Cassman's research on corn yields. If you really want to get educated on the determinants of corn yield check out his work. Link to his webpage: agronomy.unl.edu/cassman
