May 1, 2004

Wheat

Wheat diseases such as Wheat Streak Mosaic Virus, High Plains Disease, Barley Yellow Dwarf Virus, Leaf Rust, Stripe Rust, and Septoria Leaf and Glume Blotch have made this a challenging production year. Several fields have combinations of these diseases and some yields reduced by more than 50 percent.

In several fields in Jones and Haskell Counties wheat plants have symptoms that you would expect to see if freeze injury occurred in the Heading (Example 1 and Example 2) or Flowering Stage (Example 3). However, the National Weather Service records show that the temperature has not dropped below 32 degrees since February 26 (March and April temperatures from Abilene).

Example 1 shows awns with white tips. Awns can be tightly held or trapped in the wheat plant auricles causing the head to push through the leaf sheath.

Example 2 shows a damaged head that has no grain. Color can range from yellow to white.

Example 3 shows wheat heads that were effected during flowering. The blank in the center of the head indicates that it occured early in the bloom period. Blooming starts in the middle of the head and then moves to the top and bottom portion of the head.

Lack of soil applied herbicides, herbicides applied later than recommended, flushes of weeds emerging after application, poor weed control, and favorable weather conditions promoting weed growth have resulted in several weedy small grain fields. Producers may be asking about harvest aids to use to burn down these weeds prior to harvesting the crop. Linked is information to assist you in answering those questions.

The harvest of wheat will soon begin. As you harvest samples from variety tests, please record the information on the foot of drill row(s) harvested and the number of inches from drill row to drill row. I will need this information to calculate the yield per acre. The thrasher is located at the Research and Extension Center at San Angelo. You may want to team up with another county to thrash samples. It takes at least two people to do the job efficiently. After the thrashing of grain is complete, the grain weights can then be entered into a spreadsheet and the information you want determined. Also, at the time of harvest you may want to get the production information from your demonstration cooperator.

Jones county has been added to the list of counties with Hessian Fly. For the counties that have Hessian Fly, you may want to let producers know of cultural practices they can use to reduce the population of the insect pest. 1) Don't spread the problem--be sure that harvesters are clean before they leave the field. 2) Turn the residue under a minimum of nine inches. 3) Planting wheat after November 1 helps reduce the problem. 4) Select resistant varieties to plant next season. Linked is a list from 2003 that gives a rating of the resistance of wheat varieties to Hessian Fly, Leaf Rust and Stem Rust. This information will be updated as we evaluate wheat plots in May.

NOTE: The heat of a controlled burn is not hot enough to kill the insect at or below the soil surface. Burning wheat stubble would only get rid of the organic matter--not the insect.

Producers that are keeping seed for planting purposes next year need to closely inspect the acreage being harvested. If weeds or diseases are a problem, they will have to have the seed cleaned, bagged and treated with the appropriate fungicide.

Cotton

Several areas across the district has had significant rainfall events after pre-plant incorporated herbicides were applied. In some instances this may reduce the amount of protection you would expect from your "Yellow Herbicides". If producers are planting conventional varieties they may want to consider using a pre-emerge herbicide at the time of planting.

During cotton production programs this spring it was stressed that producers planting Liberty Link Cotton need to make some modifications to their sprayers. Ignite herbicide is a contact material and requires a minimum of 15 gallons of water per acre to get adequate coverage of the material on the plant. Coverage is critical anytime a contact pesticide is used!

I want to thank Stephen Biles, Michael Brooks, Sam Fields, Warren Multer and Tommy Yeater for their assistance in obtaining, sorting and distributing cottonseed for District 6 and 7 variety tests.

From all indications we better be ready for insect pressure. As the wheat dries down, there will be a significant increase in thrip. The wild host plants growing in the ditch provide a good home for a number of insects. I am expecting to see a lot of fleahoppers this season.

Over-the-top glyphosate herbicide applications to Roundup Ready Cotton needs to be made before the fifth true leaf stage. Roundup applied to tolerant varieties has a slight impact on the cotton. Applying Roundup incorrectly can be a costly mistake. Some known negative impacts include: 1) thickening of the anther sack which reduces the plants ability to release pollen and which results in reduced seed production (since lint forms on the seed coat then lint production is reduced also); 2) reduced stamen length which results in reduced pollen deposition on the stigma which results in reduced seed production; 3) disorientation of the cells in developing seeds which result in low vigor seeds being produced. Roundup is a beneficial tool when used correctly.

The soil temperature this season has been warmer than usual. The weather station located east of San Angelo records soil temperature of an unplanted area at the 2 and 6 inch soil depth. Temperatures collected are available for viewing from the San Angelo Web Page. The URL is http://sanangelo.tamu.edu/weather/2004/. The minimum temperature for planting cotton is a ten-day average of 600 F at the 8 eight inch depth. This temperature is taken at 8:00 a.m. each day. Cotton planted in warm soil, usually germinates and emerges faster and are healthier plants.

Insect Scout School

The annual cotton insect scout school will be held June 1, 2004 at the Texas A&M Agricultural Research and Extension Center at San Angelo. After the half-day training, the Extension Scouts will be travelling to Uvalde, Texas to fine-tune their scouting skills. Contact Rick Minzenmayer at (325) 365-5212 for more information.

Pesticide Recertification Training

On May 10, there will be a training conducted at Abilene for producers needing to obtain a Private Applicators license. For more details and to register for the meeting call Gary Bomar at (325) 672-6048.

Weed Identification


Clammy Groundcherry
Physalis heterophylla

Picture submitted by
Rick Minzenmayer

Malta starthistle
Centaurea melitensis

Scarlet Gaura
Gaura coccinea

The weeds shown are actively growing at this time. Each small picture is linked to a larger picture.

Monthly Calendar

May

May 3, District Office, Office Conference
May 6, McCulloch and Concho Co., Wheat Field Day
May 7, Taylor and Callahan Co., Wheat Field Day
May 7, Taylor and Callahan Co., Wheat Task Force Meeting
May 7, Jones County, Wheat Field Day
May 11, Brown County, Ag Natural Resources Day
May 14, Coleman County, Wheat Tour
May 20 &21, Tom Green County, Youth Program on Cotton
May 21, Tom Green County, Professional Ag Workers
May 26, Coleman County, District 7 TCAAA Meeting
May 27 &28, Annual Leave

June

June 1, District Office, Insect Scout School
June 7, District Office, Office Conference


Sincerely,


Billy E. Warrick
Extension Agronomist
Texas Cooperative Extension
Texas A&M University System