Bibliography Tag: weed management systems
Tom Polansek, “EPA to allow use of dicamba next year, but with safeguards,” St. Louis Post-Dispatch, September 19, 2017.
SUMMARY:
This story reports on the EPA’s decision to allow dicamba use in 2018, although with yet to be determined additional rules to mitigate damages. The acting chief of the herbicide branch Reuben Baris is quoted that “ensuring the technology is available” is the top priority, but that the agency wants to ensure that it is “used responsibly.” This echoes Monsanto’s argument that the fault lies with applicators and not their product. While a cutoff date similar to the one proposed in Arkansas (April 15) is one of the options considered, it is considered unlikely as it would not achieve EPA’s goal of “maintaining dicamba’s usefulness.” FULL TEXT
Tom Polansek and Emily Flitter, “EPA eyes limits for agricultural chemical linked to crop damage,” Reuters, September 5, 2017.
SUMMARY:
More details on proposed EPA regulatory action ahead of 2018 growing season to address dicamba damage crisis. EPA is considering a cut-off date in spring or early summer for dicamba applications, allowing pre-emergence spraying only. The agency calls the extensive damage of this season unacceptable and warns of “significant changes” to the rules. This will impact Monsanto’s bottom line: “If the EPA imposed a April 15 cut-off date for dicamba spraying, that would be catastrophic for Xtend – it invalidates the entire point of planting it.” Article also notes the high cost of dicamba seed as farmers try and decide the benefit of ordering the resistant seed. ” Dicamba-tolerant soybeans cost about $64 a bag, compared with about $28 a bag for Monsanto’s Roundup Ready soybeans and about $50 a bag for soybeans resistant to Bayer’s Liberty herbicide.”
FULL TEXT
Robert J. Kremer and Nathan E. Means, “Glyphosate and glyphosate-resistant crop interactions with rhizosphere microorganisms,” European Journal of Agronomy, 2009, 31:3, 153-161, DOI: 10.1016/j.eja.2009.06.004.
ABSTRACT:
Current crop production relies heavily on transgenic, glyphosate-resistant (GR) cultivars. Widespread cultivation of transgenic crops has received considerable attention. Impacts of glyphosate on rhizosphere microorganisms and activities are reviewed based on published and new data from long-term field projects documenting effects of glyphosate applied to GR soybean and maize. Field studies conducted in Missouri, U.S.A. during 1997–2007 assessed effects of glyphosate applied to GR soybean and maize on root colonization and soil populations of Fusarium and selected rhizosphere bacteria. Frequency of root-colonizing Fusarium increased significantly after glyphosate application during growing seasons in each year at all sites. Roots of GR soybean and maize treated with glyphosate were heavily colonized by Fusarium compared to non-GR or GR cultivars not treated with glyphosate. Microbial groups and functions affected by glyphosate included Mn transformation and plant availability; phytopathogen–antagonistic bacterial interactions; and reduction in nodulation. Root-exuded glyphosate may serve as a nutrient source for fungi and stimulate propagule germination. The specific microbial indicator groups and processes were sensitive to impacts of GR crops and are part of an evolving framework in developing polyphasic microbial analyses for complete assessment of GR technology that is more reliable than single techniques or general microbial assays. FULL TEXT
Jack Kaskey and Lydia Mulvany, “Creating a Problem- And a Lucrative Solution,” Bloomberg, September 5, 2016.
SUMMARY:
Discusses the herbicide treadmill and how it has sparked the development of, and demand for, dicamba-resistant technology. FULL TEXT
Environmental Protection Agency, “COMPLIANCE ADVISORY: High Number of Complaints Related to Alleged Misuse of Dicamba Raises Concerns,” August 2016.
SUMMARY:
EPA and state agencies have received an unusually high number of reports of crop damage that appear related to misuse of herbicides containing the active ingredient dicamba. Investigations into the alleged misuse are ongoing. This Compliance Advisory is intended to provide information on the agricultural and compliance concerns raised by these incidents. FULL TEXT
Benbrook Consulting Services, Use of Dicamba on Crops as Surveyed by the National Agricultural Statistics Services (NASS), 2016.
SUMMARY:
Table detailing NASS reports of dicamba use (percent of total crop) and application rates. FULL TEXT
Monsanto, “Monsanto, UNL Sign Agreement to Develop Dicamba-Tolerant Crops,” Monsanto Press Release, March 23, 2005.
SUMMARY:
Monsanto press release announcing agreement with University of Nebraska-Lincoln to develop dicamba-resistant crops. FULL TEXT
Monsanto, Monsanto Meeting Whistle Stop Tour – Day 1, Monsanto Official Transcript, August 17, 2016.
SUMMARY:
Detailed transcript of Monsanto investor meeting in August 2016 where dicamba and glyphosate investments and projections were discussed. FULL TEXT
Jack Kaskey and Lydia Mulvany, “Monsanto Seeds Unleash Unintended Consequences Across U.S. Farms,” Bloomberg, September 1, 2016.
SUMMARY:
Reports on dicamba damage in 2016 after Monsanto allows sales of dicamba-resistant crops even though the EPA had not yet approved the new dicamba formulations meant for use with the new GE seeds. Farmers tell Bloomberg they feel “compelled to buy the engineered Monsanto seed to avoid injury next season.” FULL TEXT
Tom Barber, “Dicamba Drift and Potential Effects on Soybean Yield,” AGWatch Network, July 7, 2016.
SUMMARY:
Tom Barber, an Extension Weed Scientist at the University of Arkansas, posts a chilling overview of what he has observed in soybean fields in several parts of the state. His piece “Dicamba Drift and Potential Effects on Soybean Yield” contains an ominous warning – “We have observed a 10% [soybean] yield loss from dicamba at rates as low as 1/1024X of the labeled rate” – a very low level of drift and/or movement following volatilization. Barber also warns that low rates of dicamba drift/movement onto soybeans, especially later in the crop’s growth cycle (i.e. R3-R5) can result in carryover of dicamba in the seed…triggering problems if the soybeans are used for seed in the next year and increasing dietary exposure levels. FULL TEXT
