The harvest cluster weight method is based on the number of producing vines per acre, the average number of clusters per vine, and the average cluster weight at harvest from previous years to predict the yield in tons per acre for the current season.
The lag phase cluster weight method is based on the number of producing vines per acre, the average number of clusters per vine, and the average cluster weight at the lag phase state of the grape with the use of a multiplier to predict the yield in tons per acre for the current season. Cluster weights will double from lag phase to harvest time. The multiplier in this calculator is set at 2 but this number can vary depending on various factors.
Sampling method and amounts of samples taken to obtain averages is beyond the scope of this calculator. Accuracy counts!
The Calculator
- Select your method
- The multiplier in this calculator is set at 2 but can be changed. It only comes in play when using the lag phase method
- Row spacing in feet
- Vine spacing in feet. 3 and 4 will determine number of vines per acre
- Enter the number of non bearing or missing vines
- Enter the average amount of clusters per vine
- Enter the average weight of these clusters in lbs
The result of the calculation will be the yield in tons per acre of the grape crop.