Statewide
In our Sorghum Tip last week on Huskie herbicide, I noted overall improved weed control this Bayer herbicide offers, particularly when paired with atrazine. The advent of Huskie for Texas sorghum, however, should not overshadow the fact that a farmer’s weed control decisions about pre-plant and especially sorghum pre-emergent weed control are far more important than the options Huskie offers. In fact, pre-emerge (or PRE) weed control is the most important weed control decision a farmer will make in grain sorghum production in Texas.
Dr. Wayne Keeling, Texas A&M AgriLife Research weed scientist in Lubbock, notes that although Huskie is a great asset to Texas sorghum farmers, our priority effort should be focused on effective PRE weed control. Our goal? — Prevent weeds in the first place, especially during sorghum emergence and early growth. Then post-emergent (POST) weed control (Huskie, dicamba, Ally, Permit, 2,4-D, etc.) can focus on controlling escapes as needed. Furthermore, if PRE weed control is good, producers may be able to delay needed POST control by 1-3 weeks to provide a longer window of either direct control of existing weeds or extending residual control further into the growing season.
Also, because Huskie herbicide largely relies on atrazine to enhance weed control, there is a concern, especially on more coarse soil types like sandy loam to reduce total atrazine rates especially if rotating to cotton the next year. PRE control can be accomplished with other chemicals, including mixes with reduced rates of atrazine, so that your field ‘loading rate’ of atrazine does not create rotation issues (especially cotton next year) when you pair atrazine with Huskie.
Below are several PRE options. Talk to your chemical supplier or company representative to further refine your PRE management strategy, especially if you anticipate needing mid-season or POST weed control options. (*) requires safened seed (e.g., Concep III, Screen) for chloroacetamide herbicides.
- Propazine (Milo-Pro) as Pre-plant or PRE (no incorporation except in rare cases)
- Individually, s-metolachlor* (Dual Magnum, etc.), alachlor* (Micro-Tech, Intrro), or acetochlor* (Warrant)
- s-metolachlor* or alachlor* in combination with reduced rates of atrazine (e.g., Bicep II Magnum, Cinch ATZ, Bullet, Lariat, etc.), which should still allow suggested POST atrazine rates when paired with Huskie
- Dimethenamid* (Outlook), possibly mixed with atrazine (Guardsman Max)
- Saflufenacil (Sharpen), possible mixed with dimethenamid* or reduced atrazine rates; Verdict* is a saflufenacil/dimethenamid pre-mix.
For a recent summary of grain sorghum weed control options in Texas, consult “Quick Guide for Weed Control in Texas Grain Sorghum—2013”, http://lubbock.tamu.edu/programs/crops/sorghum/. Notes for saflufenacil (PRE) and trifluralin & diuron (POST) as well as harvest aids will be added this spring.
