As we move into planting activities this year most folks are aware that we have limited deep soil moisture in the Coastal Bend of Texas. Moreover, most farmers are always looking for ways to reduce input costs to their respective crops, whether it be fertilizer, trips across the field or herbicide application. Another area that cotton farmers might consider to help reduce input costs is that of seeding rates.
Recent research indicates that farmers can not only get by with a few less seed per foot of row, but also that returns on investment may be equal to or better than higher rates. For the last two years I have conducted a seeding rate study with Darrell Lawhon in Nueces County using Liberty Link Cotton varieties. We looked at 2, 4, and 6 seed per foot of row planting rates. In 2011 we planted FM 835LLB2 in this test. Actual plants per foot of row were 1.6, 3.1 and 3.9, with seed cost ranging from $34 to $102 per acre.
There was not a statistical difference in lint yield per acre between the three treatments. However, when seed cost per acre is considered, the 4 seed per foot treatment shows an economic advantage of $13.20 per acre over the 2 seed per foot and $53.89 per acre over the 6 seed per foot treatment. A similar trial conducted in 2010 also showed that the 4 seed per foot density was the most economical. A detailed report can be viewed at this web site; http://nueces.agrilife.org/files/2011/08/Lawhon-plant-pop-study.pdf
Another important factor when planting cotton is soil temperatures. In fact, cotton should be planted according to soil temperatures not the calendar in South Texas. The optimum soil temperature for cotton planting is 65 degrees at the seeding depth at 8 a.m. for three consecutive days, with a 5-day favorable weather forecast. Temperatures of 60 degrees are acceptable with a favorable forecast. Recent cold fronts have resulted in the soil temps dropping into the upper 50s for a few days.
Local soil temperatures are monitored by a Crop Weather Program maintained by Texas AgriLife Research in Corpus Christi. The soil temperature data is available online via the web at the following web site; http://cwp.tamu.edu/.
Once in the site select the Pre-planting Soil Temperature tool and then select the nearest weather station to your farm. This tool is provided at no cost to users.
Good stand establishment is not only affected by soil temperatures, but also seed-to-soil contact. One key to good seed-to-soil contact is to make certain that press wheels work well and are aligned properly, suspended, free-rolling and clean. Having one press wheel with a smooth surface and the other with a spiked surface can improve seed-to-soil contact and reduce potential crusting.
Seedling disease can also affect stand establishment and is caused by several species of soil fungi. Environmental factors that favor these disease include: soil temperatures less than 65 degrees, cold and wet conditions after planting, and poorly drained soils, just to mention a few. Controlling seed and seedling diseases are for the most part preventative rather than rescue treatments. Preventative measures include crop rotation, quality seed, timely planting and fungicides. Today most commercially available seed is treated with fungicides, so the more control measures that are implemented, the better disease control will be achieved.