Strategic Farming: Field Notes discussed prevent plant and late planting decisions

 Angie Peltier and Liz Stahl, Extension educators - crops, and Phyllis Bongard Extension educational content development and communications specialist

Prevent plant field 2019. Photo: Liz Stahl

On June 8, 2022, Dr. Seth Naeve, UMN Extension soybean agronomist and UMN Extension ag business management educator, Dave Bau, joined UMN Extension educators Liz Stahl and Ryan Miller for a discussion about how to objectively evaluate options for fields that haven't been planted yet. Is it better to plant soybeans or elect to take a prevented plant payment?  What are some of the adjustments one should consider when planting soybean late? These and other issues were addressed in the fifth episode of the 2022 Strategic Farming: Field Notes program. 

To listen to a recording of this episode subscribe to Strategic Farming: Field Notes on your favorite podcasting platform or visit this website: https://strategicfarming.transistor.fm/#.

Wet weather caused planting delays

According to the USDA’s National Ag Statistics Service weekly crop progress and condition report issued on Monday, June 5, Minnesota’s corn farmers have made a lot of planting progress despite the slow start. Corn planting as of June 5, 2022 was 93 complete, just slightly behind the 5-year average of 96%. However, with just 72% of the 2022 soybean acres planted, soybean planting is significantly behind the 5-year average of 90%.

A tool to help farmers choose between two less-than-ideal decisions

During the long Minnesota winter, farmers make preparations to ensure all their crop’s needs will be met. When field conditions dictate that a crop cannot be seeded before the final planting date for crop insurance, one could choose to plant a different crop, plant during the 25-day late planting window and accept a lower insurance guarantee or elect to take a prevented plant insurance payment.

To help crop producers compare and contrast among these different options, UMN ag business management educators created a spreadsheet in which a producer can plug in current crop prices and their own production costs to decide which option is most economical favorable. Current new crop cash prices for corn on June 8 were $6.60 for corn and $14.80 for soybean. A producer also adds their actual production history (APH) and planting date to the spreadsheet so that the model factors in the lower yield potential associated with late planting and determines the revenue potential of a late planted crop.

If a farmer thinks that they are going to take a prevented plant payment, their first point of contact should be their crop insurance agent. Insurance agents can then help determine which of their enterprise’s covered crops is most lucrative to claim and make sure that all the correct paperwork makes its way to the Farm Service Agency (FSA) office and the insurance adjustor by mandatory deadlines.

If one elects to take prevented plant payments, how would APH be affected?

APH is the average yield for a crop over the last five production years. Should one elect to collect prevented plant payments, no cash crop will be planted and so there would be no 2022 yield that would go into determining APH. Conversely, if one decides to plant during the 25 day late planting window, they should know that 2022 yields will be used calculate the new APH for next year. With crop prices as high as they are, there is a large pull for most farmers to do what they can to plant a crop during the late planting period.

What adjustments should one consider when planting soybean after June 10?

Soybeans planted around June 10 have 75% of the maximum yield potential that would have been achievable had they been planted on time. In late planted soybeans in southern and central Minnesota, one can anticipate an approximate yield potential penalty of 1 percent per day in June. This lowered yield potential is approximately ½ bushel per day during the beginning of June and approximately 1 bushel per day during the second half of June.

Relative maturities

The top adjustment one should consider making for late planted soybeans is maturity. In an effort to diversify risk producers normally plant a range of soybean relative maturities. The very small yield penalty encountered with planting a very full-season variety is typically small enough that people have begun to shift toward later maturity varieties. Although June 10 is the traditional date to switch to a shorter-season variety (~ 0.5 relative maturity units earlier) folks that originally planned to plant very full season soybeans, should have switched to a shorter-season variety by around June 1. If one was more conservative and planned to plant varieties in maturity groups earlier than ‘2’ in southern Minnesota and 1 to 1.5 in central Minnesota, they could stick with their original variety selection a little longer than June 10. 

When attempting to switch to an earlier-season variety, be sure that the variety has characteristics you are looking for. Switching from a full-season soybean variety with a high yield potential to an earlier variety with poor yield potential that is only available because no one wanted to plant it, would not be doing yourself any favors.

Overall, the yield penalty and hassle associated with planting later maturities is lower than in corn, where low test weight and high grain moisture at harvest are two potential headaches one could encounter with planting a full-season hybrid late. However, if a full-season soybean meets an early frost, the risk of harvesting green seed is not zero.

Row spacing and seeding rates 

There can be a tiny benefit for planting late soybeans in narrower rows and at higher seeding rates, but this isn’t always observed. Narrow rows and higher seeding rates typically provide a yield advantage regardless of planting date, but this advantage can be slightly higher with later planting dates. The UMN Extension recommendation is to not make a change away the original seeding rate and row spacing to chase a slight yield advantage that may or may not materialize in 2022. Also, soybeans planted late are less likely to encounter cool and wet conditions that can impact emergence and necessitate a seed treatment and/or higher seeding rate as those planted in a timely fashion.

What would you recommend for those that typically roll their soybeans?

Some farmers like to roll their soybean fields after planting to smooth the soil surface so that they can set their combine headers lower to harvest the lowest pods. Rolling soybean after seeding tends to have the most benefit and least risk when fields have a lot of residue from previous crops. When fields with very little residue from the previous crop are rolled, rolling carries low value and very high risk. No one should consider rolling very wet fields or field patches as these areas are most likely to crust over and negatively impact seedling emergence and final plant stand.

Weed management considerations

Sunday, June 12, is the final day that farmers south of I-94 in Minnesota can apply an approved dicamba formulation to dicamba-tolerant soybeans. The cutoff date north of I-94 is June 30. However, there is also a temperature restriction throughout the entire state; dicamba formulations for use on dicamba-tolerant soybeans cannot be applied when temperatures are above 85° F or forecasted to be above 85° F for the day. The Minnesota Department of Agriculture has recently reminded pesticide applicators that these restrictions remain in force despite planting delays.

Those that planted Xtend-flex varieties have some flexibility to be able to use Liberty after June 12 or 30. Using pre-emergence herbicides (Group 14 and 15) with residual activity is also a good strategy, but labels should be consulted because there are some active ingredients that should be avoided when planting late due to carryover concerns. As is the case every year, following label recommendations regarding adjuvants and targeting small weeds (smaller than 4 inches tall) is likely to provide the best control.

What about if one is considering growing soybeans after soybeans?

Planting soybeans after soybeans is not a recommended practice due to disease issues. Many years of growing soybeans with the PI88788 source of soybean cyst nematode (SCN) resistance every-other year has led SCN populations to evolve to better reproduce on soybeans with this source of resistance, resulting in higher SCN population densities and more SCN-related yield losses. If one is considering planting soybeans after soybeans, try and plant a variety with the Peking source of SCN resistance and if none are available consider a nematocidal seed treatment (ex. ILeVO).

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Thanks to the Minnesota Soybean Research & Promotion Council and the Minnesota Corn Research & Promotion Council for their generous support of this program!