By MINDY POEHL | Central Texas Edition

The crowd at the Williamson County Crops Tour learns about different sorghum varieties. — Photo by Mindy Poehl

July 6, 2006 - Information on plots of corn, cotton and sorghum was readily available at the Williamson County Crops Tour that was held June 27, in Granger. 

To determine which varieties are best adapted to the growing conditions in Central Texas, an eleven variety corn plot was planted and observed. This year, the corn crop “saw average to below average growing conditions, with yields averaging from 72 bushels per acre to 98 bushels per acre,” explained Robert Bohac, with Crops Allied Industry Companies.

All of the varieties had Roundup Ready and Corn Rootworm technology.

“Cropland Genetics 721 CRW/RR2 was an entry with the yield range of 80 on the East side; 84 in the middle; and 81 bushels per acre on the West side,” stated Bohac.

The herbicide program used on the plot consisted of Clarity at 8 ounces and Atrazine at 1.5 pounds per acre pre-emergence, and Roundup at 22 ounces per acre post-emergence.

Corn variety Triumph 866 RR suffered very little rootworm damage.  — Photo by Mindy Poehl

According to Bohac, there was not a significant amount of rootworm infestation in the plot. Samples were taken at harvest time and aflatoxin tests were conducted.

Dyna-Gro CXO 5215 CRW had an aflatoxin test of 400, a bushel weight of 53.7 and a yield of 98 bushels per acre. Garst 8226 CRW/RR had an aflatoxin test of 200, a bushel weight of 52.3 and a yield of 89 bushels per acre. Triumph 1536 RWRR had an aflatoxin test of 570, a bushel weight of 52 and a yield of 83 bushels per acre. 

In the cotton plot, 20 boll weevil pheromone traps were monitored throughout the 2005 growing season. The average boll weevil trap catches ranged from .2 to 0 weevils per trap per week. The mean average for the cotton season was .063 weevils per trap per week, “which was down slightly from the previous season with an average of .15 weevils per trap per week for the same monitoring period,” explained Bohac.

The traps were monitored once per week during the cotton season and the trap line provides data to evaluate the progress of the boll weevil eradication program.

“A comparison of trapping data before eradication and each year of the eradication program can provide a relative measure of the impact of the eradication program on weevil numbers during the spring when weevils are emerging,” said Bohac. “Boll weevil numbers remained low throughout the monitoring period.”

The highest weekly trap catches were obtained on May 20 and September 24 when 10 and 9 weevils were captured. Weevil catches quickly decreased in late May and remained low until early August when cotton began to mature and weevils were forced to move in search of more favorable host fields.

An 18-variety grain sorghum plot was also planted to determine which varieties are best adapted to the area. After planting, moisture became a limiting factor in the yield, which ranged from 3,542 to 2,308 pounds per acre.

Dyna Gro was used as a check and it yielded 2,344 pounds on the East end, 2,308 pounds in the middle and 2,669 pounds on the West end. 

“There was no significant difference in the land across the plot,” said Bohac. “The planted population was 74,200 seeds per acre. In addition, 2 quarts of Expert per acre was used at planting as a herbicide. And, all of the varieties were treated with Cruiser or Poncho seed treatment.” 

Production practices and cost of production were equal for all varieties. 

“Seed prices, which is the only variable between equally maturing varieties, do not differ significantly among seed companies,” explained Bohac. “Therefore, producers should look for varieties that perform well over a several year period and various environmental conditions.” 

Standability was rated at harvest on a scale of 0-5 with 0 being all standing and 5 representing a significant number of plants being down. Pioneer 84 G 62 showed the highest yield at 3,542 pounds per acre, followed by BH Genetics BH 3822 at 3,458 pounds per acre.