Replanting Considerations

By Jonathan Kleinjan

Every season weather events such as hail or flooding can damage or destroy previously planted crops in all or in portions of fields. In May or even early June, many producers will replant these areas. As the end of June approaches, the window for replanting narrows and producers may want to do a more careful evaluation of whether or not to replant.

Check Crop Insurance

The first step in a replanting decision is to check with crop insurance providers to ensure policy compliance. This is probably not an issue if replanting drowned out pockets within a field to the same crop. However, if switching crops (i.e. from corn to soybeans) or replanting a hailed out field of soybeans, crop insurance regulations may be an important consideration. For example, after a hail storm, crop insurance companies may require a waiting period (10 days or so) prior to evaluating a soybean crop for potential replanting.

Assess Crop Damage

The second step is to assess the crop damage and remaining stand. The extent of damage should be assessed 3 to 5 days after the event or when a few days of favorable growing conditions have returned. Good yield potential (~90%) still exists when stands are reduced by 20% for both corn and soybeans. However, stands should be somewhat uniform and the remaining plants should be healthy. A stand of corn planted in early May that is reduced from 35,000 plants per acre to 20,000 can still achieve approximately 80% of its final yield potential.

Soybeans are even better at retaining yields with reduced stands. Most research suggests that a uniform final stand of 80-100,000 plants per acre is enough to obtain expected yields. If final stands are less than 80,000 or there are several bare spots in a field, a producer may want to ‘fill-in’ these areas with a row-crop planter. Keep in mind that adequate moisture must be present for these ‘fill-in’ soybeans to germinate and that the existing stand will be damaged by this process. The second planting will also have lower yield potential due to a later planting date. University research suggests that ‘filling-in’ does not increase yields over leaving existing stands if there are more than 66,000 plants per acre.

Consider Profitability & End-Use

Finally, consider the profitability and end-use of the crop prior to replanting. Early maturing corn planted after June 10 will only retain about 65% of normal yield potential and may not even achieve physiological maturity if weather conditions are not favorable. However, if a producer is able to use forage crops, late planted corn can still provide an excellent silage crop.