Residual soil nitrogen levels last year were relatively high and extremely variable from field to field. That means the Late Spring Nitrate Test (LSNT) can generate a large return on investment for in-season nitrogen decision-making this year. For those making in-season nitrogen applications, there may be significant opportunity for savings on fertilizer inputs.

Early-season field conditions can set the tone for the entire growing season. Two common soil issues that can limit early crop development are soil crusting and sidewall compaction. While they look different in the field, both restrict crop establishment and early root growth, reduce early vigor, and can make crop stress symptoms show up sooner and more severely.

Iowa State University Extension and Outreach Field Agronomists have completed their spring survey of subsoil moisture in northwest Iowa. Subsoil moisture sampling in Iowa dates to February 1954 when ten sites were chosen for soil moisture sampling. In 1959, the sampling increased to 22 locations, and in 1971, 61 locations were sampled. Today, 18 locations are sampled in northwest Iowa.

Residual soil nitrogen levels may be higher than average heading into 2026 due to the relatively warm winter, meaning some fields may need less sidedress N fertilizer than in a typical year. The Late Spring Nitrate Test (LSNT) can be used to reduce uncertainty in N fertilizer needs, lowering the risk of both under and over application. 

Spray drones are increasingly being evaluated by Iowa farmers as an additional tool for crop input application. When used appropriately, these systems can provide flexibility for timely applications, reduce field traffic, and improve access to areas that are difficult to reach with traditional ground equipment.