Pre-pruning may be considered as an approach to help control total pruning costs, allow for some disease management by waiting until disease risk is lowest and frost protection by delaying the onset of bud break in the spring.
Mechanized pruning considerations could include electronic and pneumatic (hand shears) or tractor mounted implements used to finish or pre-prune a vineyard block.
General Concepts in Prepruning Include:
Common measures of optimal pre-pruning length are: 12-15 inches (30-40cm), Length 6-8 internodes
Reasons for pre-pruning vary: there is some thought of controlling costs, disease and frost control (up to 2 weeks) by allowing for a later finish pruning pass. If vine disease impact is reduced, the effective life of a vineyard may be extended.
A grower may choose to pre-prune mechanically or by hand. If by machine, field conditions for access, possible compaction, cost of equipment & R&M are to be considered.
Pre-pruning is generally applied to Cordon and not Cane pruned blocks.
If mechanized pre-pruning, consider the buildup of debris in the vine row which may eventually lead to pest and disease control issues. (See mulching action in the video below.)
There may be vineyard infrastructure (negative) impact from cut wires, broken posts and stakes that will need repair following a mechanized pre-prune pass.
Some trellis systems and vineyard row spacing will allow for hand pre-pruning only.
- Typically a pre-pruning machine on the north coast will prune one row at a time. Timing may become an issue depending on the condition of the equipment and skill of the operator.
Narrow Vineyard Avenue width and hillsides (<15-17%) will limit the use of a pre-pruner.
When incorporating early season pre-pruning as a management strategy, later Season (finished) pruning is possible. This may allow a grower to use less (hand) labor by giving workers additional time to finish a vineyard.
Worker safety is always an issue around mechanized operations however hand labor pruning presents additional challenges with workers comp around the strenuous and costly activity of hand pruning.
Contact Walsh if you would like professional advice on quality mechanization of your vineyard: