Author Archives: Michael Flessner

Herbicide Resistant Weeds Workshops Slated for Maryland, Virginia, and Delaware

A series of half-day workshops will be held in Maryland, Delaware and Virginia this winter for farmers interested in learning about the problems of herbicide resistant weeds and how to manage them. Hosted by University of Maryland Extension in collaboration with Virginia Tech and University of Delaware, these workshops are designed to equip farmers with the knowledge to improve weed control on their farms.

Farmers in the mid-Atlantic area are starting to see the impact of herbicide resistant weeds on their crop yields. With many problematic weeds now found throughout the region it is essential that farmers learn the key management strategies to control these weeds.

Sessions will cover integrated weed management tactics; palmer amaranth, common ragweed and marestail control strategies; and developing a weed management plan. There is no charge to attend and lunch will be provided. Pesticide (commercial and private) and CCA continuing education credits will be offered.

Workshop locations and times are listed below. Please RSVP to the respective meeting location to provide an accurate meal count.

February 25th (12 pm to 5 pm) Old Beale Sanctuary, 369 Queen Street,Tappahannock, VA 22560

To register call the Essex County Extension Office: at (804) 443-3551

February 26th (8 am to 1 pm) St. Mary’s County UME Office, 26737 Radio Station Way, Leonardtown, MD 20650. To register call the St. Mary’s County UME Office at 301-475- 4484

March 4th (8 am to 1 pm) Harrington Volunteer Fire Company, 20 Clark St, Harrington, DE 19952. To register call the UD Carvel REC, at 302-856-2585 (ext 540)

March 5th (8 am to 1 pm) Somerset Extension Office, 30730 Park Drive, Princess Anne, MD 21853. To register call the Somerset County Extension Office at 410- 651-1350

March 6th (8  am to 1 pm) Frederick County UME Office, 330 Montevue Lane, Frederick, MD 20712. To register, call the Frederick County UME Office at 301-600- 3576

March 7th (8 am to 1 pm) Chestertown Volunteer Fire Company, 211 Maple Ave, Chestertown, MD 21620. To register call the Kent County UME Office at 410-778- 1661

For more information contact Ben Beale at 301-475-4481, Michael Flessner at 540-315-2954, Matt Morris at 301-600-3578 or Mark VanGessel at 302-856-7303.

Dicamba Training Opportunities

If you intend to apply Engenia, Xtendimax, or FeXapan this year, you need to complete the annual dicamba specific training requirement in addition to being a certified pesticide applicator. In Virginia, this training is conducted by the registrants (manufacturers), but can also be completed in another state including registrant training, state mandated training, and state approved training. Both in person and online training is acceptable. Training is not product specific; you do not have to take the training from the registrant of the product you apply.

Make sure to document your training.

Here are links to find a training event near you or complete online:
BASF

Bayer

Corteva

University of Nebraska

Please note that some some events require pre-registration.

The following links are under revision for 2019 but will be useful shortly:
Mississippi State Extension

EPA Registration Decision for Dicamba Use in Xtend Soybeans and XtendFlex Cotton

As you may have heard, the EPA announced Wednesday (Oct. 31, 2018) to continue dicamba registrations for over-the-top use in Xtend soybeans and cotton, through 2020, with label changes. This decision only impacts Xtendimax, Engenia, and FeXapan dicamba products. The decision does not impact dicamba products that are not labeled for over-the-top use in Xtend soybeans or XtendFlex cotton.

Summary of label changes from the EPA:

  • Two-year registration (until December 20, 2020)
  • Only certified applicators may apply dicamba over the top (those working under the supervision of a certified applicator may no longer make applications)
  • Prohibit over-the-top application of dicamba on soybeans 45 days after planting and cotton 60 days after planting
  • For cotton, limit the number of over-the-top applications from 4 to 2 (soybeans remain at 2 OTT applications)
  • Applications will be allowed only from 1 hour after sunrise to 2 hours before sunset
  • In counties where endangered species may exist, the downwind buffer will remain at 110 feet and there will be a new 57-foot buffer around the other sides of the field (the 110-foot downwind buffer applies to all applications, not just in counties where endangered species may exist)
  • Clarify training period for 2019 and beyond, ensuring consistency across all three products
  • Enhanced tank clean out instructions for the entire system
  • Enhanced label to improve applicator awareness on the impact of low pH’s on the potential volatility of dicamba
  • Label clean up and consistency to improve compliance and enforceability

Source: https://www.epa.gov/ingredients-used-pesticide-products/registration-dicamba-use-dicamba-tolerant-crops

A more detailed press release with links to more information from the EPA is here: https://www.epa.gov/newsreleases/epa-announces-changes-dicamba-registration.

Annual dicamba-specific training is still required for the use of these products, in addition to a private or commercial pesticide applicators license. Therefore, training completed in 2018 needs to be repeated to legally apply in 2019. In Virginia, trainings will delivered by the registrants (BASF, Bayer, or Corteva) both in-person and online. I will post further details on when, where, or how to schedule a training as these details become available. Training requirements to apply these products in North Carolina were different than Virginia for 2018, which I anticipate will continue in 2019.

In the past, Virginia Department of Agriculture and Consumer Services Office of Pesticide Services has not placed additional restrictions, beyond the EPA approved federal label, on these products. I do not anticipate a change in that stance for 2019.

2018 Weed Management Field Day

Mark your calendar and plan to attend!

June 19th, 2018

8:30 to 11:30am

Highlights:

• View over 100 herbicide plots
• The latest corn and soybean herbicides
• Nozzle selection
• Herbicide resistant Palmer amaranth and common ragweed control options
• Integrated weed management tactics
• Free coffee and doughnuts!

Location:

Southern Piedmont AREC
Field entrance near:
1200 Darvills Road
Blackstone, VA 23824

Google Maps link to field entrance: https://goo.gl/maps/iKZmYnjx7wM2 

Please register by email: flessner@vt.edu

More information in the flyer: 2018 Weed Management Field Day Flyer

Herbicide Resistant Common Ragweed Plot Tour

Having trouble controlling herbicide resistant common ragweed? Make plans to attend the field tour, this coming Thursday (June 22nd, 2017) near Lawrenceville, Virginia. Complete information is below. Please RSVP as soon as possible.

View a complete spectrum of preemergence and postemergence herbicides in soybeans in the field to see what works best for yourself. Also, learn about integrated weed management approaches that work within our cropping systems. 

Scout now for marestail/horseweed

Recent mild temperatures and the mild winter are setting the stage for rapid development of marestail/horseweed (Conyza canadensis) this spring.  Marestail was particularly troublesome last year in soybeans.  Marestail can germinate in both the fall and the spring. It is more likely to overwinter in the rosette stage during mild winters.  If you wait until your typical burndown the marestail may start bolting and therefore be more difficult to control. Adding to this difficulty, many marestail populations are resistant to Roundup (and other glyphosate containing products). You should scout your fields targeted for soybeans now to identify overwintering marestail.  Marestail control can be achieved with 2,4-D  or dicamba now and still offer plenty of time to avoid plant back restrictions (up to 15 days for 2,4-D or up to 28 days for dicamba). Glyphosate resistant weeds and the difficulty in controlling more mature weeds underscore the need to scout fields earlier and use some alternative herbicides in your program.  Always consult the product label for specific instructions.

TriCor Receives Registration for use in Wheat and Barley

The herbicide TriCor, a metribuzin product from United Phosphorus Inc., has received 24(c) registration (special local needs) for use in Virginia for control of Harmony and Harmony Extra (group 2 herbicides) resistant common chickweed. The supplemental label is here: TriCor DF Herbicide 24(c) VA label. This is good news for small grains growers.

Research by Drs. Scott Hagood and Michael Flessner indicate that TriCor at 2 oz/a results in excellent common chickweed control when applied in fall or spring, with no significant injury to wheat. However, wheat injury can be a concern. Using crop oil concentrate or vegetable oil surfactants with TriCor increases the risk of crop injury, as well as when applying with fertilizer in combination with TriCor. Growers should select wheat and barley varieties that are tolerant of metribuzin if planning on using TriCor as certain varieties are more sensitive to metribuzin than others. Seed dealers may have information regarding metribuzin tolerance. Additionally, preliminary nonreplicated wheat variety sensitivity research by Drs. Wade Thomason, Carl Griffey, and Michael Flessner is included in this publication: https://pubs.ext.vt.edu/CSES/CSES-129/CSES-129-PDF.pdf. See pages 99 to 101.

Always make sure to read and follow the product label. Also note that TriCor is the only stand-alone metribuzin product legal for this use.

Example of wheat variety differences in sensitivity

Example of wheat variety differences in sensitivity to metribuzin. Thomason 2015.