Extension Agent: Ag tour shows results of herbicide treatment of huisache
May 31, 2011 at 12:31 a.m.
By Brian Yanta
The Texas AgriLife Extension Service in Goliad County hosted its Agricultural Tour at the Julie Wimberly Memorial Homemaking Building at the Goliad County Fairgrounds on Friday.
More than 40 producers attended.
The primary focus was targeting huisache or Acacia farmesiana.
Last year, starting in May, herbicide experimental treatments were applied targeting huisache. Plots were sprayed both individually and via broadcast methods.
Applications were made every month from May to November. This plot is located about three miles north of U.S. Highway 59 on Franke Road. The plot signs will remain up for the rest of this week if you would like to view them.
The plot plan is also posted on line at goliad-tx.tamu.edu.
A couple of disclaimers: although the results look promising, all there is at this point are some recommendations from Dow Agro on how to use the product in certain applications. None of these treatments are listed in our extension publication B-1466 nor is the plant huisache even listed on the GrazonNext label. Hopefully, with this year's work of data and other plots around the state, Dow will be able to change this.
Also, it is not recommended to go out and start spraying the product. The Extension would like to have at least two year's worth of data before they say if it is effective in killing the plant.
Results are showing the the application window may be open to include early summer treatments. From an economics point of view, the GrazonNext treatments are comparable to that of Grazon P+D, and from a practical point of view, this makes scheduling an application more convenient.
Preliminary ratings show about a 90-95 percent efficacy on our individual spot treatments on both huisache and black brush acacia.
Broadcast treatments are rated around 85 percent for the May treatment and a 80 percent rating for the October treatment. The final rating will be conducted next spring. Currently, you can see some re-sprouting on both IPT treatments and broadcast treatments. There is some flagging on broadcast treatments. But looking at the ratings, you can see these are on very few plants in number.
Why is aminoprylid showing such good results on these two hard-to-kill species? Benny Martinez, with Dow Agro said his "ah-ha" moment was after a tour to Mexico and looking at a product labeled in Spanish containing the active ingredient aminopyralid.
"I looked at the label and it was Next labeled for IPT treatments for blackbrush. That's when I knew we had something," Martinez said.
The B-1466 manual has always recommended fall treatments for huisache. Fall is usually the time plants are shutting down. They are producing carbohydrates and translocating them to the root zone to store through the winter. When you spray chemicals then, they are being carried down, as well. Contrary to this popular belief, activity is being seen with aminopyralid in the early summer, when the plant is actively growing and healthy.
Martinez tries to explain, "I think that's why we have had inconsistent results with this pest [sic] huisache because of its ability to get diseased and its susceptibility to insects in the fall."
Fall is typically the time you see heavy insect pressure on the plants. "One of the most common is the twig girdler. This insect hosts in huisache and can cause the plant to stress. Basically, the plants are in a better state of health in early June, following spring rains, than they are in October and November."
There were also talks from Farm Service Agency Executive Director Robert Garcia and Natural Resource Conservation District Technician Kirby Sauer, who both gave agency updates. Garrett Baacke with Winfield Solution spoke on adjuvants and how they can help your herbicide applications when included in your tank mix.
Of course, this tour could not be possible without the assistance of ANR committee members: David Boyd, Delfino Castro, Robert Garcia, Luis Hernandez, Jim Kreneck, Tommy Natho, Ralph Ramsey, Mike Reagan, Manual Vela and Louis Worsham.
Sponsors were Ag Workers Auto Mutual Insurance, American Bank, Braman Winery, Capital Farm Credit, Dow AgroSciences, Winfield Solutions, Goliad County Sheriff's Department, Hartman Distributing and Wylie Sprayers.
Brian Yanta is a Goliad County Extension agent.