By Anthony Hanson
The ninth session of Strategic Farming: Field Notes for 2026 was held on July 15 covering corn reproduction and nitrogen use and availability, especially considering the hot weather and localized heavy rainfall in some areas of the state. Ryan Miller, Crops Extension Educator, discussed these topics with Jeff Coulter - Extension Corn Agronomist, and Brad Carlson - Extension Educator in Nutrient Management.
Corn
Coulter mentioned that crop development has progressed quickly this season with tasseling happening about a week ahead of normal. Consistent moisture across much of the state has kept stress on corn to a minimum, but it is starting to dry out with little chance of rain looking forward.
A couple questions were asked about the effects of the recent heat dome and high heat on corn. In general, corn tolerates the low 90s fine, but upper 90s and dry conditions can stress corn, especially around pollination. Under these conditions, tassels develop quicker and pollen may shed before all silks emerge. Conditions in southwest Minnesota are more prone to stress corn currently due to persistent drought conditions.
High temperatures can also affect pollen viability. In the mid-90s pollen viability begins to drop significantly, and around 100°F corn pollen dies. Generally this not a major concern in Minnesota, and temperatures generally did not approach this range outside of the Twin Cities heat island.
Source : umn.edu