There was a definite delay in plant maturity with the lower plant population, but no significant difference in yield in any of the years in which these tests were conducted, he says.

In the lower plant situations, the bolls were larger and micronaire was higher. In some areas with a tendency to having high micronaire cotton this can be significant.

Calendar date is important. Cotton that would be replanted in early May might not need to be replanted by late May.

Variety selection and calendar date are directly linked. It is not a good idea to plant a full-season variety if the replanting date is past May 15. An early-maturing variety will do better when the season is shortened because of a late planting date.

Knowing the health of surviving cotton plants, both above and below ground, is critical to making sound decisions about replanting.

How healthy the remaining plants are will have a direct bearing on the profit potential of the field of cotton.

If replanting is necessary, continue to use insecticides and fungicides, especially if the first stand died from seedling disease.

Use a burn-down herbicide to kill the old stand of cotton and any weeds that may have emerged on the row.

There are plenty of theories on when to replant cotton because of low plant populations. The best probably comes from University of Arkansas Cotton Specialist Tom Barber, who says, “If you have enough cotton left to make the decision difficult, you probably have enough to keep.”

Based on research in the Southeast over the past 10-20 years, another criteria to use is: If you have 10 to 13 skips that are 3 feet or longer in 80 feet of row, then a replant will be justified.

In some cases a grower may “spot-in” areas of the field with his planter, however in many situations spot planting is not recommended because late-season management will be more difficult.

Though Jones’ research in South Carolina suggests even lower plant populations may produce comparable yields than the ideal 3-4 plants per foot of row, another popular theory on replanting is: 20,000 plants per acre range, or as low as 1.5 plants per row-foot with no or few skips.

If the stands are broken with numerous skips, replanting is in order at populations below 30,000 plants per acre, depending on the size and frequency of skips.

At the end of the day, each grower has to make his or her own decision on whether to replant a field of cotton. Knowing exactly what has happened to a field of cotton from the time it’s planted until a grower decides whether to replant is the ultimate criteria for making such an expensive decision.

rroberson@farmpress.com