Southwest cotton farmers have a plethora of management decisions to make in the last few weeks before they begin planting. One could be the decision not to plant too soon. As days warm up and winter wanes, producers need to firm up acreage, variety, planting date and seeding rates and fertility. Randy Boman, Oklahoma State University Extension cotton state leader, offered some tips recently at the annual Carnegie Cooperative Cotton conference in Carnegie, Okla.
Boman says variety selection decisions to reduce production risks should include:
- Agronomy — Yield stability under all water regimes. Quality, storm resistance, plant type. Maintain diverse herbicide programs and/or cultivation to manage weed resistance.
- Plant Pathology — Knowing the disease or nematode species in a particular field is vitally important. (RKN, Fusarium, Verticillium and bacterial blight resistance, tolerance or immunity).
- Entomology—Insect resistance for lepidopteran pests. (Bollgard II, WideStrike, TwinLink, and WideStrike 3).
PLANTING DATE AND RATE
Planting procedures are also important and could set the stage for the rest of the season. Boman offers this advice:
- Achieving an adequate stand is the first objective in cotton production. We have new, improved planters that provide excellent down-the-row seed placement for proper spacing. Planters also have excellent vertical control to place seed at the proper depth.” With the cost of cotton seed and the current low price for cotton, seeding rate also deserves attention, he says.
- Avoid extremely early planting.
- The optimum plant population for 40-inch rows is around 2 to 4 plants per foot of row. So, what seeding rate do you use to get there? Target the lower end for dryland. Target the higher end for irrigated. What percent of seed planted will make it to harvest?
- The planter and the seed matter. Growers must have faith in the planter settings, as well as the seed quality. Agronomically, it’s difficult to justify planting less than 2 seed per foot of row in dryland production.”
- Seeding rate trials across several locations and years indicate that from two-thirds to three-fourths of the seed dropped at planting will produce a plant that is there at harvest time, Boman says, but “weather could make a difference.”
Growers also need to look at fertility, especially nitrogen, Boman says. “Annual deep soil sampling for nitrogen should be routine, partly because of the potential for excess nitrogen, which increases cost as well as posing production problems such as:
- Increased Verticillium wilt disease.
- Increased cotton aphid populations.
- Increased plant growth and plant growth regulator need.
- Delayed maturity.
- Challenge for harvest aid performance.
- Ultimately negatively affect fiber quality — micronaire, and possibly bark and leaf grade.
- Cotton production losses, extremely high expenses or both.
“I see more cotton fields with too much nitrogen rather than too little,” he says. “One bale of cotton requires about 50 pounds of nitrogen. Some of that demand may be met with residual nitrogen (NO3) in the soil and irrigation water, so those sources should be tested and accounted for in the nitrogen fertilizer application.”
Foliar fertilization may be justified in cases where in-season deficiencies appear, he says. “I have seen dryland cotton yields double when zinc deficiency is corrected with extremely timely foliar application — but timing is very critical.
For the latest on southwest agriculture, please check out Southwest Farm Press Daily and receive the latest news right to your inbox.
However, the expense of supplemental nutrition on a healthy crop is hard to justify, he says. “Texas studies also have not shown a profitable response to supplemental nutrition to a healthy crop, and that seems to hold beltwide. The first nutrient priority is soil fertility.”