Replant Decisions

Know the factors affecting whether or not to replant.

By Dr. John P. Beasley, Jr.
Extension Peanut Agronomist, University of Georgia

Reasons For Inadequate Stand:

• Planter not calibrated correctly
• Planted too deep or too shallow
• Lack of soil moisture
• Soil temperature too cold
• Seed damaged from handling
  or exposure to high temperatures
• Seed quality problem
• Seedling disease

Replant Considerations:

• Timing - When is the replant decision being considered? Will there be time for the crop to reach maturity?

• Reasons - What was the reason for the initial inadequate stand, and can that be corrected in a second crop? Is seedling disease present?

• Goal - Is it better to partly replant where needed, or should I rework the field and completely replant?

• Conditions - Are the current conditions adequate for planting? Is soil moisture readily available?

Environmental conditions in the early part of the 2007 growing season were extremely undesirable for peanut planting, with the driest spring on record. Many producers had to decide whether or not to plant at all. Some producers decided to take their chances that conditions would improve.

While some areas of Georgia did receive sufficient rainfall to plant in early June, other areas, especially the southwest corner, never received adequate rainfall for planting. Some growers that planted had very minimal plant emergence.

The decision then became, “Do I replant?”

When this question arises and the decision is being made in mid-to late-June, there is a much higher risk that replanting that late will result in the crop not reaching optimal maturity.

The other situation is when planting occurs during the early to middle part of the planting window, and there is a marginal stand; then the decision to replant comes up.

Skips No More
Fifteen years ago, a stand with a few skips in the field could still make respectable yields. With the increase of tomato spotted wilt, this is no longer possible. Getting a good stand of peanuts, initially and quickly, is an important part of obtaining high yields and grades. A final plant stand of four or more plants per foot of row is the desired goal.

Sometimes things go wrong, such as planters not calibrated correctly, planting too deep or too shallow, not enough soil moisture or cold soils. Peanut seed are among the most delicate seed to handle. Rough handling or exposing seed to extremely high temperatures can have an adverse effect on seedling vigor and emergence. Find out as much as possible about the seed you have purchased, including seed count per pound and germination percent.

On occasion, there may be a seed quality problem. You should save an unopened bag from each lot of seed you have planted until the end of the planting season. If there is a question on seed quality, this may help.

Finding Optimum Maturity Difficult
The goal is to see an acceptable stand within 10 to 14 days after planting. You should do everything possible to obtain a rapidly and uniformly emerging stand of peanuts. If an adequate stand is not obtained by 21 days, do a field inspection and look for rotted or decaying seed or abnormal seedlings.

Replanting, in part, is not a complete solution to a problem, but hopefully an adequate management decision. The University of Georgia Extension Service recommendation is to offset planters 2 to 3 inches to the side of the existing row and replant with 40 to 50 pounds of seed per acre.

Replanting in the existing row is not recommended because the same problems may occur again with Aspergillus crown rot or Rhizoctonia seedling disease.

In general, replanting a shorter-maturing variety with an already emerged mid- or late-maturing variety is not acceptable. Too many environmental factors come into play to predict the outcome of this practice.

Normally, it will be extremely difficult to determine optimum maturity for harvest when there has been a replant situation, resulting in significant yield and grade loss. The more expensive, but more reliable option would be to rework the beds and completely replant the field. This practice would depend on the initial planting date and moisture availability.

Bottom line – do everything possible to avoid replanting peanuts.