Ongoing Drought - Forage and Pasture Concerns

Howdy everyone!

Texas A&M AgriLife

I'm reposting an article written by Corrie Bowen, EA-ANR agent for Wharton County, in regards to questions our offices have been receiving lately. Several of our growers have called asking about safety concerns regarding grazing fertilized grain sorghum.

2022 Drought Forage Concerns

Cotton Stalk Destruction Deadline

 Howdy everyone!

Texas A&M AgriLife

With cotton harvest in this area wrapping up and the stalk destruction deadline approaching (October 31, 2023), now is an appropriate time to go over stalk destruction methods. As a reminder, cotton stalk destruction is mandated as part of the boll weevil eradication program, which is recognized as one of the most ambitious and successful pest management systems in agriculture.

Because cotton is a perennial plant that we have adapted for annual cropping systems, the cotton plant can continue to grow even after harvest aid applications. This potential for regrowth mandates post-harvest stalk destruction to prevent development of new leaves and bolls for insect habitat and feeding. In the southern and eastern portions of the state, stalk destruction is more necessary as the warm, wet climate can ensure cotton regrowth; in the northern regions, the cold temperatures and frost will kill cotton before new fruit is produced.

Mechanical

Stalk destruction should occur as soon as field and weather conditions allow after harvest. Stalks are routinely shredded and then disked or plowed under for complete destruction. Stalk pullers can also be used to uproot stalks.

Chemical

(The information given herein is for educational purposes only. Reference to commercial products or trade names is made with the understanding that no discrimination is intended and no endorsement by Texas AgriLife Extension and Texas A&M University is implied. Always consult the label)

We are now past the spray ban date for 2,4-D this year. As a reminder, this year, the Texas Department of Agriculture (TDA) granted the temporary suspension of the 2,4-D application rule (Section 7.53(oo)(2)) in Wharton County, which allowed for the ground application of 2,4-D herbicides by permit on the west and east sides of the Colorado River in Wharton County after Thursday, September 1, 2023; and the aerial application of 2,4-D herbicides by permit on the west side of the Colorado River in Wharton County after Friday, September 15, 2023 (application of 2,4-D products with a permit on the east side of the Colorado River in Wharton County are already permitted after September 15, 2023 under rule 7.53(oo)(1)).

For Enlist, (2,4-D tolerant) cotton, 2,4-D is no longer an option to chemically destroy cotton stalks. For cotton growers with Enlist (2,4-D tolerant) cotton, they will now have the choice of using either dichlorprop or dicamba to control cotton stalks.  TDA has approved a 24(c) Special Local Need label for a dichlorprop-containing product called Duplosan by NuFarm.  This product will be equally effective on cotton varieties with the XtendFlex or Glytol LibertyLink traits. AgriLife Extension data shows that this product will be more effective than dicamba for controlling Enlist cotton.

The label rate for Duplosan is 32-48 fl oz/acre. It should be applied to stalks with some leaf regrowth in order for the chemical to successfully translocate to the roots and shoots. For best practices, shred stalks to 6-8 inches and then follow with the herbicide application as soon as possible. Some growers choose to mount spray booms directly on their shredders to band the herbicide during shredding, which can achieve excellent results. Thorough coverage is essential for herbicide efficacy.

Please note that Duplosan is an ester formulation which may volatilize and affect nearby susceptible plants. This product is a state limited use pesticide that requires a pesticide applicator license or direct supervision of a licensed pest applicator for purchase or application of this product. The 24(c) label will expire December 31, 2023.

Links:

Texas Boll Weevil Eradication Program

Stalk Destruction Information

Weekly IPM audio updates

Have a great week,

Sarah Marsh

IPM Extension Specialist

Producer/Grower Surveys - Response Requested

 Howdy all!

We are seeking feedback regarding our audio newsletter specifically from our growers who listen to the IPM Audio Updates (which are tagged at the end of every post). We are interested in knowing more about our clientele, and your response would be very much appreciated!

For this area (Gulf Coast), here is the link to the Blacklands Upper Gulf Coast Grower Survey. The surveys are very short and consist only of 3 questions.

Have a great week,

Sarah Marsh

IPM Extension Specialist

Weekly IPM audio updates

Watch out for Armyworms

 Howdy everyone!

We've been moving into cooler weather and with the moisture we've received, remember to keep an eye out for fall armyworms. Some reports of small (2-3 instar) worms have made their way to our office.

 

Photo by Sarah Marsh (2018)

Armyworm Injury

Fall armyworms can inhabit multiple different hosts but feed primarily on bermudagrass, ryegrass, sorghum, and wheat​. Defoliation typically occurs from August to November, with injury appearing on the edges of the affected areas and traveling in as the worms "march" on once resources are depleted.

Injury from small larvae can appear as "windowpaning", but as larvae progress through the instars, defoliation rapidly appears. Fields may have a "frosted" appearance.

Photo by Holly Davis

 

Photo by Alabama Extension

Scouting

Armyworm scouting should occur every 2 weeks at minimum. For ideal scouting conditions, check areas in the early morning or evenings when the larvae are most active and feeding. 

There are multiple methods to scout for armwyorms. The simplest is to simply get down to ground and look in the grass or soil.  On hot days, the larvae may be on the undersides of leaves or even in the top layer of soil, hiding from the heat.

Sweep nets are very effective for collecting samples in tall grass. Another method is to run your hands across the grass in a 1-2 square foot area, knocking the worms to the soil, and count the larvae that are dislodged.

Regardless of the method, knowing the number AND size of the worms is important to determine the economic injury potential. Worms smaller than 1/2 inch are considered younger instars and are not as injurious as worms sized larger than 1/2 inch. The economic injury threshold for pastures and hay fields is 2-3 worms sized 1/2 inch or longer per square foot OR 2 worms per sweep. The threshold is not exact, but larger numbers of smaller worms also qualifies.

Control

(The information given herein is for educational purposes only. Reference to commercial products or trade names is made with the understanding that no discrimination is intended and no endorsement by Texas AgriLife Extension and Texas A&M University is implied. Always consult the label)

Control measures should always take into consideration several factors. If the field is being used for hay, harvesting as early as maturity allows is a option to try to prevent further defoliation. However, the larvae may still feed on the cut grass.

Chemical control is one of the best tools in the fight against armyworm infestation. In Texas, there are 47 products registered for use in bermudagrass against fall armyworm. The cost, efficacy, hay and grazing restrictions, and days residual varies amongst all products. Always consult the label; the label is the law. When making application choices, consider the economic injury threshold and incoming weather conditions; there are only a few truly rainfast options available, such as Prevathon, Vantacor, or Besiege, all of which contain chlorantraniliprole. These products are more expensive but do produce longer-lasting effects. 

For additional questions about FAW control, please reach out to your local County Extension Agent, IPM Agent, or Extension Entomologist. Always use an insecticide according to the label.

Texas A&M AgriLife Extension Service is not responsible for insecticide applications, damages, or other issues encountered.