Keauhou Ranch Koa Forestry
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Transcript of Keauhou Ranch Koa Forestry
Keauhou Ranch Koa Forestry
Nick KochForest Solutions Inc
• Scarification: High elevation, 1970s
• Planting: Low elevation, 2000’s
Two reforestation methods
• Grazing
These uses allowed Kamehameha Schools to fulfill its education edict
• Koa harvest
Legacy of extractive use 1950s-90s
• Intensive logging on1,200 acres (40-60 ac year)– Clear-cut– Seed tree
• Cattle excluded
Late 1970s-90s: Experimentation
R Skolmen, USFS
• Vigorous germination of koa following scarification
Clear-cut &seed tree =same result
Scarification: Results
1 yr
R Skolmen, USFS
• Scarification is highly effective with an existing seed bank
Excellent response
P Scowcroft, USFS
Early growth rates were high
P Scowcroft, USFS
& few crop trees
High basal area
Result: 23 years later
• Scarification is successful when seed source is immediately present
Result: 20-30 years later
Kilauea Forest Reserve
(Not harvested)
Keauhou Scarification
More thinning is needed to ensure there are more of them!
Crop trees show some promise
Result: 34 years later…
• Periodic thinning is needed
• Forest inventory and stocking guides form the basis for thinning decisions
• Rotation length will be between 40 and 60 years
• Limited harvest entries earlier
Active management is required
P Scowcroft, USFS
• Kamehameha Schools began planting koa trees in the 1980’s as part of its educational program
• In 2005, Forest Solutions began planting koa at a rate of 40-60 acres per year
• This effort continues to date
1980s – Today: Planting in pasture
• Grass / competition control• Site preparation• Planting• Fertilizing• Stem form improvement• Thinning
Steps for planting & maintenance
Grass control manual /mechanized
Site preparation – spot (2006 –today)
Site preparation – row (2011)
• Seeds are collected from superior trees in Keauhou Ranch
• Seed collections are kept refrigerated in air tight containers
• A seed lot number is used to track provenance
Seed collection & documentation
Seedling production
Inspecting seedling quality
Applying agro-gel & water
Dibble planting in spot cultivated field
Planting
• Planting quality is essential to early development
• Inspections– J Root– Too deep– Too shallow– Angle planted
Planting quality control is key
• Small amount of fertilizer is applied just after planting
• Objective is to boost early growth and reduce weed control needed
• We are working on studying the effect, if any of fertilizers, which may not be needed
Fertilizer: Boost early growth
• Early growth rate of one inch diameter per year
• Already tapering off by year 6
• Coincides with canopy closure
• Wet side and dry side areas display different growth rates
Growth rates – variable
• Remove competing leaders only
• First entry at 10-12 months
• Last entry at approximately two years
Stem form improvement
To avoid this outcome
P Scowcroft, USFS
So what about cost?
Pre-plant weed control, 58.3974099554836, 3%Spot cultivation Wilco,
198.300283286119, 11%
Seedlings and planting, 679.117766086604, 37%
Post plant fertilizer 1, 190.292998785917, 10%
Singling 1, 84.0145690004047, 5%
Pruning 1, 140.024281667341, 8%
Aerial broadcast control 2, 183.318494536625, 10%
Pruning 2, 140.024281667341, 8%
Aerial broadcast control 3, 89.0651558073654, 5%
Pruning 3, 70.0121408336705, 4%
Total = 1,838
• Disease– Koa wilt– Psyllids
• Fire– Rare but catastrophic
• Weeds– Thrive on neglect by land managers
And threats?
Pests
Fire – and other events
Invasive weeds
• Scarification works well where an existing seed bank is present
• It is not a panacea– Still need to thin – though later– Still need to select for form– Still need some weed control
• Active management is needed!
Summary: Scarification
• Planting works well in areas where seed bank is depleted
• Best suited for high quality sites • Needs intensive management early on• Is an interim step toward true uneven-age
management• Improved seed sources are desperately needed
– Wood quality and stem form are highly heritable
Summary: Planting
Scarification & planting are not mutually exclusive1. Scarify an area2. Set out a series of plots to check recruitment3. Plant into open areas4. If open areas become too large, revert to plantation
establishment
Summary: Combination
Questions?