More Information for Midsouth Soybean Producers
On Feb. 6, 2024, a federal court in Arizona vacated registration of three dicamba products that had been approved for over-the-top application to soybeans by the US-EPA in 2020. This decision is discussed in several articles that are linked below.
Court Vacates Dicamba Registrations [Progressive Farmer].
Federal court revokes dicamba approval [FarmProgress].
#plant24 confronted by vacated dicamba ruling [FarmProgress].
Dicamba Court Order Puts Farmers in Immediate, Costly Bind [American Soybean Association].
Soy Growers Implore Administration to Help Farmers Amid Dicamba Decision [American Soybean Association].
Midsouth soybean producers are encouraged to access the content in these articles so that they are up-to-date on what this decision means and how it can potentially affect their ability to combat hard-to-control troublesome weeds in their fields. They are also encouraged to stay abreast of the latest happenings regarding this decision and its future developments.
Feb. 14, 2024 Update: In a news release from ASA titled “ASA Applauds EPA Existing Stocks Order for Dicamba Ahead of Soy Planting”, the announcement is made that the US-EPA “has declared farmers can accept ‘existing stocks’–previously registered pesticide products currently in the U.S. that were packaged, labeled, and released for shipment prior to the Feb. 6 court ruling–” of dicamba. The existing stocks order also clarified that dicamba products already in the possession of distributors, coops, and other parties for sale before the Feb. 6 date of the cancelled dicamba registration can be sold and distributed, within set guidelines specified in the order. ASA also asks for the administration’s support of an appeal of the Feb. 6 ruling.
Feb. 15, 2024 Dicamba Update: On Feb. 14, 2024, the US-EPA issued an Existing Stocks Order for Dicamba Products Previously Registered for Over-the-Top Use on Dicamba-Tolerant Cotton and Soybeans, which contains the pertinent provisions for the disposition of any existing stocks of formerly registered dicamba products. Of special importance is the information in Table 1 of the above order, which contains the end dates for sale and distribution of existing stocks of dicamba products as well as the end dates for the use of those existing stocks in U.S. states. The American Soybean Association provides a concise summary of the above order and the events that led to its provisions in their Feb. 15, 2024 eBean newsletter.
In an article titled “ASA Suvey Shows Herbicide Strategy Compliance Difficult for Farmers”, ASA’s Scott Gerlt and Kyle Kunkler discuss how the US-EPA’s proposed pesticide registration plans could affect U.S. farmer’s abilities to use pesticides. ASA’s survey found that most U.S. soybean producers were not currently meeting the compliance requirements in the proposal. Previous ASA exploration found that complying with the Vulnerable Species Pilot Program and the Herbicide Strategy portions of the proposal could be prohibitively expensive for affected farmers.
In articles titled “Novel Discovery Could Fortify Soybean Cyst Nematode Resistance” from the SCN Coalition and “Gene discovery shows promise in soybean cyst nematode fight” by Pamela Smith of DTN, information is presented about a discovery that has potential for preventing SCN from infesting soybeans [Click here for scientific journal article]. The discovery involves the loss of function of a gene [SNAP02] in resistant soybean varieties that, when functional, allows SCN to access the plant–i.e. the loss of function of the gene thwarts SCN’s ability to attack the soybean plant. This discovery could immediately impact farmers who have repeatedly planted soybean varieties with resistance derived from any one source–e.g. PI 88788 and Peking–by significantly lowering SCN populations that have adapted to the resistance source. By adding a non-functioning copy of the discovered gene, resistance to the nematode will be enhanced regardless of the source of resistance. And CRISPR gene editing technology can be used to facilitate the incorporation of this new discovery into newly-developed SCN-resistant varieties. A welcome additional benefit that could be derived from this discovery is the potential of enhanced longevity of newly-developed and released soybean varieties regardless of their resistance source. Click here to access a White Paper that discusses nematode management in soybeans.
In an article titled “SCN reproduction rate increases on resistant trait” by Mindy Ward, additional information from researchers and specialists at Iowa State Univ. and the Univ. of Missouri indicates that the PI 88788 source of resistance that is currently used in most SCN-resistant varieties is losing its effectiveness. In fact, according to data in the article, SCN reproduction on varieties with resistance derived from PI 88788 went from about 25% of the SCN reproduction on susceptible varieties in 2005 to about 63% in 2023. According to Dr. Mandy Bish at the Univ. of Missouri, the trajectory of such infection on varieties with the PI 88788 source of resistance is going up. Thus, the above discovery of the function of the SNAP02 gene is very important since it applies to varieties with SCN resistance derived from myriad known sources. This will potentially add an additional layer of protection against SCN in addition to the proven practices of rotating soybeans with a non-host crop and rotating soybean varieties with SCN resistance derived from different sources.
An article titled “Evaluation of a high-speed planter in soybean production” by Kovács and Casteel appears in Agronomy Journal [2023; 1-14]. Pertinent points from that article follow.
• New planter technology has been developed that allows farmers to plant faster and more precisely than can be done with traditional planters.
• Overall, planting speed up to 10 mph using the high-speed planter selected for this study did not affect soybean seedling emergence or final seed yield.
• Plant spacing was slightly but insignificantly increased by about 6% as planting speed doubled from 5 to 10 mph.
• The authors concluded that 1) increasing planting speed within the limits used in this study can be done without negatively affecting plant population and seed yield in soybean when using new high-speed planter technology, and 2) with increased planting speed, a producer should pay increased attention to accurately setting the planter prior to the planting operation.
Articles titled “Terminate cover crops effectively”, “Robust cover crop systems for soybeans”, and “Cover Crops Support Microbial Diversity: Three Case Studies” provide the following points regarding cover crop management.
• Cereal rye as a cover crop works well prior to planting soybeans by providing biomass and weed control.
• More biomass will be realized from a cereal rye cover crop if it is allowed to grow later into the season before planting a soybean crop.
• Cereal rye that is allowed to grow to pollination or to its maturity can be terminated with either a roller-crimper or herbicides. Whatever method is used, an effective kill of the cereal rye cover crop is required so that escaped plants do not compete with the soybean crop for needed resources.
• Regrettably, a cereal rye cover crop used prior to soybean planting requires revenue from cost-share or carbon programs to have the same returns as a soybean production system without the cover crop.
• Remember that termination of the cereal rye cover crop can occur either before or after soybean planting. Terminating before soybean planting ensures that the cover crop does not compete with the soybean crop for needed resources, while cover crop termination after planting [often referred to as “planting green”] will result in the maximum biomass on the soil surface.
• Presently, cover crop costs are not offset by lowering other costs or by increased soybean yield following a cover crop. This could change over the long term if soil health is improved to a level that higher soybean yields will be realized in a production system that uses cover crops.
• Any cover crop system must be used over the long term to realize the potential/touted benefits to soil health and carbon sequestration.
• Results from research conducted in Canada, Belgium, and the U.S. support the importance of using cover crops to promote the long-term abundance and diversity of the soil microbiome, which is composed of microbes [including bacteria and fungi] that are integral to soil and plant health.
• Using conservation agriculture practices such as no-till and cover crops supports a robust soil microbiome that will 1) promote optimum residue decomposition and soil structure, and 2) consume excess nutrients from over-fertilization that will subsequently minimize nutrient runoff from cropped fields. Thus, it is essential to consider the soil microbiome when focusing on soil and ecosystem health.
Click here and here to access articles that provide details about the Plant-Soil Microbiome and using Cover Crops.
An article titled “How Do I Conserve Groundwater While Irrigating?” provides information to remind those who irrigate of some major points to consider to ensure that water is not wasted during the irrigation process. Some of the major points in this article follow.
• Groundwater is a finite resource, and pumping of this groundwater from underground aquifers is outpacing their recharge. This means that groundwater sources used for irrigation in many parts of the U.S. are being depleted.
• The below are some ways for irrigators to conserve groundwater in sources that are used for irrigation.
• Irrigate only when a crop needs the water. This involves knowing a soil’s water holding capacity and a crop’s critical period(s) of need so that proven irrigation scheduling tools–e.g. soil sensors, ET-based scheduling, plant-based scheduling–are used to schedule irrigation.
• Do not over-saturate the soil with irrigation water if rain is in the forecast.
• Explore deficit irrigation if water is in short supply.
• When water is in short supply, replace high water-use crops in a rotation with those that use less water.
• Always be willing to incorporate the latest proven technology into any irrigation system that is used.
Click here to access a White Paper on this website that presents information about soybean water relations and irrigation, and here to access the Mississippi Soybean Irrigation Guide.
Composed by Larry G. Heatherly, Feb. 2024, larryh91746@gmail.com