Late Planted Drought Stricken Soybean II: More Valuable as a Forage or Green Manure?

Now that we have checked the label and determined we can legally harvest our soybean crop as a forage now lets consider the calendar for our full suite of options. The average number of days it will take from R6 (full seed) to R7 (beginning maturity) soybean is 15-18 days. If you are in R6 now look at your historic killing frost date and extended weather forecast. If the odds are in your favor roll the dice and cut the beans for grain. If you are not at R6 yet or there is a strong chance of a killing frost in your extended forecast prior to R7 lets realistically consider our options for best utilizing this standing soybean crop.

Option # 1: Soybean haylage considerations

  • What is my realistic tonnage expectations?
    • Late planted drought stricken soybean will yield ~1 to 2 tons of dry matter per acre.
  • What is it going to cost me to harvest and put this crop up?
      • Mowing ($11.45 per hour)
      • Swathing ($13.50 per hour)
      • Haylage (chopping/hour/ ft head width; $12.71)
      • Hauling ($ not listed))
      • Fill silage bags ($10.15 per foot of bag)
  • How should I price this crop?
    • Soybean silage pricing will fall between good quality hay ($233.10 per ton) and poor quality hay ($112.50 per ton); personal communications from P. Hoffman and R Shaver.  Source: FeedVal 2012 predicted dairy feed prices and rankings for August 2013. V.E. Cabrera, P. Hoffman, and R. Shaver.
    • If you were to price the soybean forage based on expected grain yield (assuming the crop would mature) and CBOT then realistic yield levels would range from 12 – 18 bu per acre at $14.35 per bu. Expected forage value range would be $172.20 to $258.30 per acre. 

Option #2: Green manure considerations

  • I am tired of throwing money at this crop……….
    • Though you will save on harvest costs the average cost of a plow down disk operation is $16.05 per acre.
  • How much will I save on next years fertilizer bill?
    • By not harvesting the crop you will not remove the 30# P and 85# K (estimated removal rates of P2O5 and K2O for 15-25 bu per acre soybean grain and straw (A2809)).
    • You may contribute 20-40 pounds of N to next years corn or wheat crop. 
  • I need the feed so this is not an option (please refer back to option #1 above).

Neither of these prove to be particularly attractive options. However I would encourage growers, crop consultants, and nutritionists to weigh the true economical value of each option carefully before proceeding.