Replanting is something farmers rarely want to think about, let alone in December. However, having a plan now can make for less of a headache in the late spring.
Dekalb Asgrow Technical Agronomist Jim McDermott said creating a replanting threshold in the winter can make the decision on whether or not to salvage a crop due to weather-related issues easier.
“When it comes to replant, it’s about trying to avoid it in the first place,” McDermott said. “It’s all about picking the right time to plant.”
McDermott noted there are multiple factors to consider when putting that plan together, but planting date is one of the easier to manage. Watch the three-to-five day forecasts going into planting.
“If there’s a cooling trend coming in, especially with cold rain in the forecasts, that’s a red flag,” he said.
If the crop struggles to get a good start, population counts are a good place to start if the crop hasn’t gotten off to a good start with dry soils. If the crop was off to a decent start but knocked down due to a hail or wind storm, look at how much is still up.
He said if someone needs to plant in less certain weather, soybeans may be the way to go.
“Soybeans are a lower risk to go in the ground,” he said. “They can have some stand loss and it’s not going to affect us on yield as much as corn.”
When issues strike and the crop takes a turn for the worst, the first item to evaluate is stand count, McDermott said. Factor in date as well as overall stand counts to see what kind of yield potential the crop may still have.
“If you are planting between April 20 to May 5, and you have a 35,000 stand, that’s considered 100% yield potential,” McDermott said. “If you are in that same window and it’s a 20,000 stand, that’s potentially 1n 89% yield potential.”
Overall population isn’t the only consideration, however, as stand will also have an affect on the crop canopy. McDermott said having less cover on the crop will impact the way weeds are growing, which will also drag down yield potential.
“If it’s a light stand or spotty stand, we may have to deal wtih more weed potential, especailly later in the season.”
Seeding rates are also important for areas being replanted, McDermott said. Typically, rates will stay similar for corn, as the goal is to continue growing a full crop for the season. However, the main impact could be on ferilizer as a later planting will affect any schedule already put in place by farmers.
“Let’s say it’s June 5 and most of the data says it’s a window of 50-60% yield potential, and we are forced to replant, that will affect applications,” he said. “We really cut back, because we have a lower yield potential.”
The same logic plays into herbicide and fungicide applications as well.
“Time can carve into the window of residual herbicide efficacy, which means a possible change in crop programs,” he said. “Always consider the additional costs of labor, fuel, herbicide and seed, and offsetting revenues when evaluating the total economic decision.”