The near-completion of the 2017 harvest signals the end of this production season. Thus, now is the time to start/complete activities in preparation for the 2018 growing season. Below are major activities/practices/decisions that should be next on the agenda in preparation for the 2018 crop.
Sampling for nematodes should occur soon after harvest. With soybeans now being rotated with corn and cotton or being grown on soils previously cropped with cotton, analysis of soil samples should be conducted to determine if soybean cyst nematode, root knot nematode, and reniform nematode are present in soils that will be cropped to soybeans. This knowledge will determine management options that should be used to reduce their detrimental effect. Click here and here for up-to-date information pertinent to this process.
Soil Sampling for Nutrient Status
With the consistently high soybean yields that have been harvested in Mississippi over the last 5 years, mining of soil nutrients will be increasing. Thus, soils that produce these high yields will have lost considerable amounts of nutrients during a crop year. Intense monitoring of nutrient removal is required in these production systems to ensure that necessary nutrients are replenished before the next crop cycle in order to maintain nutrient levels that will be adequate to maintain these high yields. Information about proper sampling protocol is provided here. Important points to consider are:
• Sampling for nutrient levels is best done when soil moisture level is suitable for tillage.
• For spring-planted crops such as corn and soybeans, collect the samples soon after harvest in the fall.
• Test each field at least once every 3 years. In the case of fields that have a biennial rotation of crops, sample every 2 or 4 years following the same rotational crop at each sampling time. This provides a consistent basis for comparing fields and detecting trends over time.
• To ensure sampling consistency of nutrient removal trends across years, sample at the same time of year and following the same crop in a rotational system.
• Soil tests should be used mainly to test for phosphorus [P], potassium [K], and pH.
Fall tillage will destroy most soybean residue remaining after harvest. If tillage is not necessary to correct a physical soil condition or problem, producers should avoid all fall tillage. Two articles on this website [Tillage for Soybean Production and Managing Crop Residues] should be consulted for detailed information about how these two issues should be considered together when decisions about what type of tillage, if any, should be conducted in the fall.
A linked article on this website provides information for producers who may be considering deep tillage of nonirrigated sites. Again, this decision should be considered along with the destruction of some soybean residue that will occur. If deep tillage is determined to be an option, it should only be conducted on nonirrigated sites when the soil is dry to ensure maximum effect.
With the present and increasing challenge of controlling herbicide-resistant [HR] weeds, fall weed control measures should be considered to provide an edge going into the following growing season.
Tillage is always an option in the fall, but the resulting destruction of residue will offset some of the positive effects of controlling weeds that will have emerged at the time of tillage.
Residual herbicides applied in the fall can help control many winter weeds and weeds such as marestail that develop strong root systems through the winter. Length of weed control depends on the type of herbicide used, but several residuals provide control into late spring of the following year.
Click here for a cautionary discussion about using either 2,4-D or Dicamba as part of a fall weed control program when either Enlist or Xtend soybean varieties will be used.
Click here for information from Louisiana State University about the importance of controlling weeds post-harvest in early-harvested soybean fields. This activity is important to prevent the production of weed seed, especially those produced by HR weeds, that will replenish the soil weed seedbank even in fields that had excellent weed control during the growing season.
A relatively new concept that should be considered for controlling HR weeds is harvest weed seed control [HWSC]. Click here for up-to-date information on this subject.
Cover Crops and Crop Residue
White Papers on MSSOY contain up-to-date information about Cover Crops and Managing Crop Residues. Also, Dupont Pioneer has published articles on Managing Corn Residue and Managing cover crops in corn and soybean production systems that have useful information that supplements that in the above two MSSOY articles.
Now is the time to start selecting varieties for the next growing season. Producers are encouraged to use MSSOY’s Variety Selection Tool and to consult the White Paper that contains links to Midsouth states’ variety trial results. Both of these resources are being updated with results from these states’ 2017 variety trials.
Click here for a link to Dr. Jeremy Ross’ updated “Cross Reference Guide for Common Soybean Varieties–2017” that can be used to ensure that producers are in fact selecting different varieties when they make their seed choices.
Composed by Larry G. Heatherly, Oct. 2017, email@example.com