Assess stand establishment to see if your crop is growing satisfactorily. By comparing the plant population per foot with the seeding rate per foot, you can determine if the stand is optimal, weak, or excessive.
- If the stand is weak, monitor for and identify any pests such as seedling diseases or seedling insects associated with poor stands.
- If the stand is unacceptable or if there are multiple adjacent rows without plants, your main management option is to replant.
- If the stand is excessive, thinning may be required. Dense plant populations, combined with conditions of adequate moisture and nutrients, can lead to rank growth, making the crop more vulnerable to insects and diseases. Depending on the cotton variety, a plant stand in excess of 60,000 plants per acre may require thinning.
The following table gives a general range for plant stand populations—although ideal densities are variety and condition dependent. For cotton plants growing in low vigor situations, higher plant densities may be desirable.
| Stand establishment | Plants per acre |
|---|---|
| Optimal | 40,000-60,000 |
| Weak | below 30,000 |
| Excessive | more than 60,000 |
To estimate plant population:
- Take at least 4 measurements from several representative areas of the field and average them.
- Use the table below to find the length of row that represents 1/1000th of an acre for various row widths.
- in your field, count the total number of plants in the 1/1000th acre area and multiply by 1000.
| Row widths (inches) | 1/1000 acre (row feet) |
|---|---|
| 30 | 17.4 |
| 32 | 16.3 |
| 36 | 14.5 |
| 38 | 13.8 |
| 40 | 13.1 |