LEAVING UNHARVESTED BEETS IN THE FIELD THIS FALL PRESENTS SOME CHALLENGING MANAGEMENT DECISIONS FOR 2011. Which crop to use in rotation, what type of tillage is best to speed up root degradation, how should the 2011 crop following sugarbeets be fertilized? Reports of small grain yields in past years after unharvested beets indicate no yield loss on many fields, slight to moderate yield loss (up to 5 bushel/acre) on some, and yield loss of 5 to 10 bushels or more on a number of fields.
It's very difficult to accurately document small grain yield loss without a combine yield monitor. Beets left in the field in the past were from the lowest yielding areas of respective fields. Low yield areas may have been due to ditches, depressional areas, along tree belts or beets were growing on less productive soil types in the field. These areas usually experience lower yields of any crop most years.
Excellent yields in most of the Red River Valley will likely result in leaving some beets in the field again this year. Past tillage in unharvested fields included using field cultivators, chisel plows, disks, and occasionally mold board plows. Each operation costs $5-8 per acre and has its disadvantages. The most successful practice may be no tillage or defoliation. Beets left in the soil more completely deteriorate over winter. Tops rapidly deteriorate without defoliation and will release N and other nutrients by the end of May. Beets left untilled are uniformly distributed across the field too. Tillage operations leave many beets on the soil surface that can plug ditches and culverts if spring flooding occurs. The U of MN has successfully disked and chisel plowed some fields.
SOYBEANS - are the ideal crop choice, they have no nitrogen management concerns, emphasize good stand establishment, and yields might decline in a dry year.
CORN - can have significant yield reduction due to the corn following sugarbeet syndrome (CFS), P & N management is critical, you must establish a good stand, yields could be reduced in a dry year.
SMALL GRAINS - must establish a good stand, N immobilization by roots can reduce yields since small grains require almost all their N early in the season. N management is critical, there is less risk of yield reduction in a dry year than with long season crops.
SUNFLOWER - another deep rooted crop that can suffer yield loss in a dry year, less effected by N immobilization since planted later, may require some extra N to maximize yield.
|Soybean||No special management needed|
|Small Grain||Add 25 to 30 lb/acre extra nitrogen to maintain yields|
|Soil Test Level for P or Zn||Rate of 10-34-0 Amount of (Gal/A)||N-P-K Applied (Lb/A)||Rate of Zinc Chelate (Qt/A)|
|High or Very High||5||6-19-0||1|
Contact your Agriculturist for assistance with questions on managing beets left in the field.