What will corn yields be like for the 2017 harvest? The biggest unknown now is seed weight. All the other yield components are set — plants per acre, ears per plant, rows per ear, kernels per row.

The USDA yield forecast, based on Aug. 1 conditions, was optimistic: the third highest yield and production on record for the US. However, their estimates are based on their five-year average seed weights. So, the million dollar question is: What will seed weights do? Will 2017 be like the five-year average?

Model-based corn yield forecasts (see Aug. 9 forecast) by agronomists across the Midwest suggest normal to above normal yields for many areas. The current cool weather is conducive for slowing development and extending the seed-fill period, thus increasing yield. All we need is a normal or late frost!

If you are interested in estimating your corn or soybean yield potential, we recommend videos from Nebraska Extension Educator Nathan Mueller and Extension guides published in the last week by Kansas State University and Iowa State University (see below). Also watch for the latest updates to the Corn Yield Forecasts in next week's CropWatch for an idea of what yields crop modelers expect to see this year. (Previous model-based forecasts for 2017 also are available.)