The fury continues in the farming community over the use of new formulations of the herbicide (weed killer) dicamba.
Dicamba herbicide is an ingredient in over 1100 products used to control broadleaf weeds in farm fields and around the home. More specifically dicamba is in the chlorophenoxy family of chemicals and is similar to 2-4-D in that it affects the growth of broadleaf plants and can result in their death. Some of you may know the chemical as banvel or Diablo.
It was first discovered in 1942 and eventually registered with the Environmental Protection Agency in 1967 as a herbicide (weed killer). The problem came to light in 2017 when chemical companies developed a less volatile form of the chemical which could be used in fields of specially developed varieties of soybeans and cotton to better control weeds which have become resistant to commonly used herbicides.
These newly developed varieties are resistant to dicamba but the weeds were not. Problems surfaced in several states when some of the herbicide moved offsite by volatilization or drift into neighbor’s fields of soybeans which were not resistant to the chemical. Some states like Missouri and Arkansas have passed restrictions that the chemical could not be used after July of 2017.
More recently other chemical companies have developed their dicamba formulations as well. Recently the U.S. EPA increased requirements on using the new formulations of dicamba to include them as “Restricted USE” products. This means applicators must be a licensed pesticide applicator and the label has additional restrictions determining when and how the product can be applied especially related to the weather.
Additional training will be required in 2018 as well on use of the product.
In the Dec. 5-18, 2017 issue of the OSU Ext. Crop Observation and Recommendation Network newsletter Mark Loux OSU Ext. weed specialist highlights the new restrictions pertaining to the new formulations of dicamba applied to XTend soybeansas well as Engenia (BASF), FeXapan (DuPont), and XtendiMax (Monsanto) dicamba herbicides. Looking back to 2017 Purdue weed scientists found only 48 hours of available time according to label information when the new formulations of dicamba could be applied in June in west central Indiana taking into account the weather conditions.
Similarly Mark Loux conducted a check using weather data from the Dayton International Airport information for June of 2017. His analysis found there was around 70 hours of time when the herbicide could be applied according to the label. Always apply herbicides according to the label and for more information on the article (2017-41) by Mark Loux go to: https://agcrops.osu.edu/.
Trevor Corboy the newly hired Ohio State Uniersity Extension Office Agricultural Educator for Greene County. He comes to us from Clermont County, Ohio where he worked as a Community Development Coordinator for OSU Extension. Corboy grew up on a farm in Brown County and is a graduate of OSU and the University of Florida. He was active in 4-H and FFA.
His office is on the Greene Co. Fairgrounds and can be reached at 937-372-9971 or by email at [email protected]
Jerry Mahan is a retired OSU Extension Educator Agriculture and Natural Resources for Greene County. He can be reached by email at: [email protected]