Soybean producers are faced with making decisions about essentially the same inputs every year. Oftentimes, the basic information for making these decisions is unchanged from the previous year(s).
So rather than repeating blog postings from previous years, I have listed what I consider the main subjects for consideration at planting time and have linked to previous postings on this website that contain pertinent information about these subjects. These previous postings have been checked and updated to ensure the information and links are current for the 2014 planting season.
I have taken this approach for two reasons:
1) As a reader of numerous articles in various print media and online sites, I am always dismayed to see a title of an article that sounds interesting only to find out it is just a re-hash of a past article or posting.
2) This blog post contains most of the information you will need to prepare for and conduct planting. The key is to bookmark it for future reference and use during the next couple of months so that you will have access to any of the subjects and their information sources with one or two clicks.
Varietal sensitivity to Metribuzin. With the continual evolving of herbicide-resistant (HR) weeds, preemergent (PRE) residual herbicides are increasingly being used as a component of weed control programs to control and/or delay the development of HR weeds and to introduce multiple modes-of-action. Many of these herbicides are mixes that contain metribuzin.
Varietal sensitivity to metribuzin exists, especially when varieties are planted on coarser-textured soils with low organic matter following PRE application of metribuzin, or on clay soils when the highest rate is used for enhanced control of certain weeds. Thus, producers need to ensure that their selected varieties are tolerant of metribuzin in situations where metribuzin-containing residual herbicides will be used. See the ratings for varietal screening for metribuzin sensitivity in the Weed Control section of this website.
Nematode-resistant varieties. Click here for information about the nematode pests that may affect soybeans grown in Mississippi. Information about resistance in current varieties is available from State Variety Trial publications from Arkansas and Tennessee, extension service personnel, crop consultants, seed dealers, and originating seed companies.
Planting date. Early planting is now the norm in the Midsouth. The decision of just how early to plant soybeans should be based on the safest early planting date at a particular location to avoid cold injury to emerging seedlings.
Click here for a table that gives the estimated dates of the last spring frost (36°) and freeze (32°) based on 90%, 50%, and 10% levels of probability at indicated Mississippi locations. These data should be used as a guide for choosing a safe early planting date.
Remember, soybeans will usually take 7 to 10 days or longer to emerge when planted early, so this extra time should be factored into a projected planting date to avoid a spring cold event that may damage emerging seedlings. As a producer, you must decide the level of risk you are willing to take when considering the earliest safe planting date in relation to air temperature.
Additional information that should be considered when selecting a planting date is provided in a white paper on this website.
Seeding rate. There is no perfect seeding rate for all planting conditions. However, estimates for optimal soybean plant populations provide a reasonable starting point for most conditions in the Midsouth. The University of Illinois developed a seeding rate calculator (see also Calculate your soybean seeding-rate needs that is available for the PC platform). Using this tool takes the guesswork out of this important calculation.
Seed treatments. Click here for information that has been updated to include a section on Clariva Complete Beans, which contains a nematicide component for protection against soybean cyst nematode (SCN). The most important point to remember about seed treatments is that a product that is effective against both seed- and soil-borne pathogens should be used in all situations. The extra cost for the nematicide-containing product is only justified if planting a susceptible to moderately susceptible soybean variety on a site known to be infested with SCN.
Handling bulk planting seed. Today’s high cost of planting seed makes this step in the planting process a money-saving issue. Click here for valuable tips on how to avoid damage to seed during the handling process.
Disposal of treated seed. As environmental stewardship becomes more important and necessary, the guidelines outlined here and in the linked articles should be followed.
Iron deficiency chlorosis (IDC). Iron Deficiency Chlorosis occurs to some extent in soybeans that are grown on the high-pH soils in the Black Belt region of east Mississippi. This deficiency can cause moderate to severe yield reductions. The best strategy for managing IDC is to select a soybean variety with tolerance.
Thus, producers need to ensure that varieties that are selected to be grown on suspected IDC sites are tolerant of the conditions that result in IDC. Ratings of tolerance to IDC made by the originating company are likely the best source for selecting tolerant varieties.