What is in this article?:
• Since so much is invested in a cotton crop it is absolutely imperative that we protect this investment by taking all precautionary measures to establish an optimal stand with good seedling vigor.
Planting depth critical
Utilizing optimal seeding rates and planting depths are also very important in establishing a good stand.
For cotton planted on 36 to 38-inch rows, planting at a rate of 2.5 seed per linear row foot, or a hill-dropped system consisting of 2 seed per hill with hills spaced 9 to 10 inches apart, is generally our standard planting rate (for 30-inch rows, this would equate to approximately 2.1 seed per linear row foot).
This rate generally allows for optimal plant stands, growth, canopy architecture, maturity, and yield. Reducing seeding rates below this standard could lead to poor stands, delayed maturity, erratic and inconsistent plant growth, and possibly reduced yields, even if planting larger-seeded varieties (which can result in more consistent stands and higher vigor), and/or if planting conditions are favorable.
If planting conditions are unfavorable, this rate could be slightly increased.
Some growers may also want to utilize or capture available soil moisture by deep planting. Cotton in Georgia should be planted at depths between 0.75 and 1 inch, but not greater than 1 inch. Planting on the shallower end of this spectrum is advised when encountering unfavorable soil or environmental conditions, or if surface crusting is likely.
Deep planting in unfavorable soil temperatures, or in soils that tend to crust, could lead to germination and emergence problems. Planting at depths closer to 1 inch is only appropriate when planting in good soil moisture, warm soil temperatures, and in well-drained soils without the potential for crusting.
One way in which growers can combat soil crusting is to run a rotary hoe over the seedbed after germination and before (or at) the point in which the plants emerge. This method is extremely effective in reducing potential stand losses due to soil crusting, but special considerations should be made to ensure this practice does not injure emerging plants (which may in fact reduce overall stands).
Evaluating plant stands and replant considerations: Plant stands should be evaluated very soon after emergence. Replant decisions are far more difficult to make as time elapses, and these decisions usually need to be made more quickly as the end of the planting season draws near.
Every field situation seems to be different, and there are several factors to take into account, when considering saving or replanting a sub-optimal stand, such as costs (seed, fuel, labor, additional herbicides/insecticides, time, etc.), herbicide options or limitations, the status/health of the remaining stand, how much time is left in the season to plant, delays in maturity by replanting, and yield potential of particular fields, among others.
Therefore, it is imperative to evaluate the crop and make these decisions promptly.
Small, evenly spaced and infrequent gaps between plants may have little impact on maturity, architecture, or yield. Frequent gaps of 2-3 feet or larger however could significantly impact yield and could lead to delays in maturity, as the plants adjacent to these gaps could only compensate for space by forming more outer position and/or vegetative branches or bolls.
Additionally, these plants may often produce very thick stalks to support the additional growth of vegetative branches, and if this type of plant structure is observed throughout the field, then harvest efficiency may also be affected.
Observing the size and frequency of these gaps compared to a mental “optimal stand” could help determine potential yield losses and the advantages/disadvantages of replanting.