Dicamba Being Blamed for Calcium Deficiency in Tobacco

 

There have been some questions regarding potential Dicamba drift, especially in tobacco.  Tyler Whaley with Wayne County Extension has fielded many of these calls, and says up to this point it’s been calcium deficiency.  Whaley says there are several subtle signs to tell one from another; calcium deficiency usually shows up just before or at topping during periods of rapid growth, versus Dicamba drift causing young leaves to become elongated, usually  more than calcium deficiency.  And extreme variations in calcium deficiency are common, often with plants right next to each other.  Dicamba drift will create more of a wave pattern.

Characteristics of Calcium Deficiency:

  • Symptoms usually show up just before or at topping during periods of rapid growth.
  • Severity of calcium can vary from plant to plant, one right beside the other.
  • Symptoms may actually vary depending on severity.  In some cases, I have seen downward cupping of a good portion of the leaf while other times you may see just the leaf tip having a “hooded” appearance and the rest of the leaf margin be more wavy (see calcium deficiency).  In addition, calcium deficiency can cause the upper leaves to exhibit more of a “Christmas tree” like appearance (see ca deficiency).
  • Symptoms can be heat/stress induced due to reduction in nutrient uptake and translocation in the plant.  This is not a soil deficiency since we have ample amounts of calcium present from lime and certain fertilizers.
  • Upper leaves become more normal in appearance once tobacco is topped.

Calcium Deficiency Tobacco Calcium Deficiency Tobacco

 

 

 

 

 

 

 

Characteristics of Dicamba:

  • Young leaves become elongated, usually more than calcium.
  • Upper stalk tobacco will be a very dark green color.  Calcium can be dark green too but I have also seen calcium not alter leaf color.
  • The leaf itself will be very thick.  Calcium can result in leaf thickness but usually not as severe as dicamba.
  • Leaf tips and edges curl downward, often times a lot more distinct than calcium (see dicamba 3).
  • Dicamba will cause vein distortion on younger leaves, calcium will not.
  • Leaves that come in contact with dicamba can have an “alligator back” appearance (see dicamba).  Calcium usually does not.

Dicamba Tobacco Dicamba Tobacco Dicamba Tobacco

 

 

 

 

 

 

 

The technologies we have available are sound weed management tools if they are used the correct way.  Ultimately, the applicator is responsible for any off-target movement of the applied herbicide and must follow ALL guidelines on the label.  Both the Xtendimax and Engenia labels state the following very clearly: “Avoiding spray drift at the application site is the responsibility of the applicator.”   

Bottom line: Common sense is required when using the technology.  If you see a dicamba sensitive crop (tobacco, sweet potato, cotton, soybeans, fruit trees, gardens etc…) adjacent to where you are spraying and can not afford to buy it, then you do not need to be spraying.

SC 4-H’ers Launch Pollinator Project

The South Carolina 4-H Pollinator Program began this year and is already a hit. A total of 61 participants from 17 counties are registered for the project. One component of the program, the Honey Bee Project, is gaining a lot of attention. 4-H’ers involved in the project learn about beekeeping, the basics of entomology and about pollinators. The project requires participants report on one managed colony during the project season from December to August. Youth from all over South Carolina can join become involved in the South Carolina 4-H Honey Bee project. Registration for 2018 will be held in December 2017. The cost is $40 for 4-H members and $50 for non-members.

Ashley Burns at taberp@clemson.edu.

Veterinarians in Washington to Talk About a Vaccine Bank

Swine veterinarians from across the country are in Washington, D.C., this week to tell lawmakers about the consequences of a Foot-And-Mouth Disease outbreak in the nation’s herds. They’re urging lawmakers to establish an offshore vaccine bank to help quickly control and eradicate the disease in the event of an outbreak. 23 veterinarians are making Capitol Hill visits as part of the Swine Veterinarian Public Policy Advocacy Program, put on by the National Pork Producers Council. The NPPC’s top goal in the 2018 Farm Bill is creating a robust FMD vaccine bank.


A native of the Texas Panhandle, Rhonda was born and raised on a cotton farm where she saw cotton farming evolve from ditch irrigation to center pivot irrigation and harvest trailers to modules. After graduating from Texas Tech University, she got her start in radio with KGNC News Talk 710 in Amarillo, Texas.

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