Factors for Determining the Need for Replant - June 2013
[Jeremy Ross, Extension Agronomist - Soybeans, Crop, Soil and Environmental Science. University of Arkansas Division of Agriculture Research and Extension University of Arkansas System, Arkansas Soybean Promotion Board.]
[Video shows Jeremy Ross standing in a soybean field.]
Hello, I’m Jeremy Ross, Extension Soybean Agronomist for the University Of Arkansas Division Of Ag. Today we’re going to be talking about replanting soybeans.
Today we’re in this field in Lonoke County to determine if a replant is necessary. Several things to keep in mind when trying to determine if a replant is necessary.
[Video shows soybean field and soybean plants.]
Number 1 is stand counts, stand counts are very easy to determine, going out and measuring the length of a row to determine what the stand counts are. You need to take several spots within the field. At this late in the calendar year, eighty thousand plants per acre would be the minimum I would look at keeping. Anything above that should have fairly good yields. May have a little yield decline within eighty or below, but eighty thousand would be the minimum stand count I would look at.
Number 2 would be the uniformity of the stand. What we do not want in the field is large gaps, large areas in the field that are barren or have very few plants. Those areas in the field are going to have problems with the weed pressure in the year, irrigation efficiency and also insect pressure later in the year.
The final thing to keep in mind is we’re getting close to that time in the year where we start to actually lose yield on soybean fields that are planted. Typically June 15 is that cutoff. Any day after June 15, we lose one to two percent yield loss per day in delay of planting. Once we hit the July 1st, that increase jumps up to about three to four percent yield loss per day in delayed planting.
For more information in replanting decisions or other agronomic questions, please contact your county extension office or visit us on our website.
[For more information visit www.uaex.edu. University of Arkansas Division of Agriculture Research and Extension University of Arkansas System, Arkansas Soybean Promotion Board.]