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Keauhou Ranch Koa Forestry. Nick Koch Forest Solutions Inc. Two reforestation methods. Scarification: High elevation, 1970s Planting: Low elevation, 2000’s. Legacy of extractive use 1950s-90s. Grazing These uses allowed Kamehameha Schools to fulfill its education edict.
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Keauhou Ranch Koa Forestry Nick Koch Forest Solutions Inc
Two reforestation methods • Scarification: High elevation, 1970s • Planting: Low elevation, 2000’s
Legacy of extractive use 1950s-90s • Grazing These uses allowed Kamehameha Schools to fulfill its education edict • Koa harvest
Late 1970s-90s: Experimentation • Intensive logging on1,200 acres (40-60 ac year) • Clear-cut • Seed tree • Cattle excluded R Skolmen, USFS
Scarification: Results • Vigorous germination of koa following scarification Clear-cut & seed tree = same result 1 yr R Skolmen, USFS
Excellent response • Scarification is highly effective with an existing seed bank P Scowcroft, USFS
Early growth rates were high P Scowcroft, USFS
Result: 23 years later High basal area & few crop trees
Result: 20-30 years later • Scarification is successful when seed source is immediately present Kilauea Forest Reserve (Not harvested) Keauhou Scarification
Result: 34 years later… More thinning is needed to ensure there are more of them! Crop trees show some promise
Active management is required • 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 P Scowcroft, USFS
1980s – Today: Planting in pasture • 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
Steps for planting & maintenance • Grass / competition control • Site preparation • Planting • Fertilizing • Stem form improvement • Thinning
Seed collection & documentation • 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
Planting Dibble planting in spot cultivated field
Planting quality control is key • Planting quality is essential to early development • Inspections • J Root • Too deep • Too shallow • Angle planted
Fertilizer: Boost early growth • 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
Growth rates – variable • 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
Stem form improvement • Remove competing leaders only • First entry at 10-12 months • Last entry at approximately two years
To avoid this outcome P Scowcroft, USFS
And threats? • Disease • Koa wilt • Psyllids • Fire • Rare but catastrophic • Weeds • Thrive on neglect by land managers
Summary: Scarification • 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: Planting • 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: Combination Scarification & planting are not mutually exclusive • Scarify an area • Set out a series of plots to check recruitment • Plant into open areas • If open areas become too large, revert to plantation establishment