Predicting 2018 corn and soybean harvest dates

FBN Analytics

The ideal harvest timing has been researched and debated by farmers and agronomists for decades. Questions about which fields to begin harvesting for corn or soybeans, and when, can often be answered by eyeballing field conditions, but they alone don’t tell the full story of when and where harvest is occurring.

Agronomists often use growing degree days to arrive at what they call physiological maturity of a corn crop (R6 stage in corn when maximum dry matter has accumulated), though there isn’t a standardized agronomic approach to determining the exact day to begin harvest.

So we’re taking a look at aggregated on-farm data contributed by farmer-members in the FBN℠ network to predict median harvest date—that is, the date at which 50 percent of acres have been harvested for both corn and soybeans.

corn harvest prediction datessoybean harvest prediction dseta

How are we able to make these predictions with aggregated data?

We analyzed historical growing degree days (GDDs) required between planting and harvest in different regions, and then compared how many GDDs have accumulated to date this year to the historical average at this date in order to estimate how far ahead or behind we’re tracking.

Are corn and soybean harvest ahead or behind to date?

Decidedly ahead and tracking early. Here’s how far ahead by state. The tables below show how much earlier we anticipate that harvest will begin in each state relative to the historical median for corn and soybeans.

days ahead of harvest soybeans corn

Check out our other coverage of harvest, like how yield varies depending on harvest moisture.


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