Singling, tip pruning and stem form improvement for Koa
Forest Solutions, Inc.November 16, 2012
Why is it needed?
• Acacias have poor apical dominance- Heavy lateral branching- Competing leaders
• This is exacerbated by- Psyllid attacks that kill apical
meristem- Frost / drought that also kill
tips- Open growing conditions
What is singling and tip pruning?
• Singling- Removing competitive leaders
only- Cut flush with stem of sapling- Target small (1/4” or less)
branches
• Tip pruning- Remove tips of competing
leaders only- Keep photosynthetic area- Reduce competition from side
branches
Singling and tip pruning: Cases 1 – 3
Singling
Tip pruning
Singling and tip pruning: Cases 4 – 6
Singling
Tip pruning
Singling: Before
Singling: After
Singling: Before
Singling: After
Tip pruning
Singling schedule
• Entry 1 at 10 months• Entry 2 at 16 months w/ tip pruning• Entry 3 at 24 months w/ tip pruning
• Cost- Approximately $ 80 - $ 90 per acre depending on ground
conditions
Cost consequences of insufficient pruning
• Pruning at 5 - 6 years- Large dead branches- Telescoping chain saw
necessary- Longer time per tree
• Pruning at 3 - 4 years- All live branches- Hand saw sufficient- Shorter per-tree times- More trees eligible for
pruning
Per-operator Acres / hr
Tool / Method Time/tree (min)
Trees/hr
2006‡ (200 tpa)
2007 (220 tpa)
2009 (240 tpa)
Hand saw 0.73 82 0.41 0.37 0.34Manual telescoping† 0.93 64 0.32 0.29 NAChainsaw telescoping† 0.88 68 0.34 0.31 NA† Area per time does not influence production rates because telescoping saws visit fewer trees than hand saws and can thus spend additional time at a given tree‡ Trees per acre indicates trees that must be pruned, not total stems
Personnel Production Cost
Stand Hand saw
Man. Tel.
Chn. Tel.
Acres / hr
Acres / (8 hr) day $ / hr $ / ac
2006 2 1 1 0.82 6.56 $125 $1522007 2 1 1 0.74 5.92 $125 $1692009 4 0 0 1.36 10.88 $125 $92