Method
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Strength
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Weaknes
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Single tree felling heads using shears or knives
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- Well established system
- Produces high-quality industrial wood (e.g. pulp, pellet feedstock)
- Suitable for fuel treatments in stands with low industrial value
- Potential to produce fuel chips but larger number of impurities due to needles, branches and foliage
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- Low cutting productivity and high cost, especially in the case of small-diameter stems
- Stems are not delimbed
- Need for roadside processing for industrial wood portion
- Need to dispose of biomass at roadside
- Small payloads in off-road and on-road transportation
- High transportation costs due to lower density of stems (due to the crown)
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Accumulating felling heads
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- Multiple-tree processing
- High cutting productivity and lower cost, especially in small-diameter stands
- Potential to produce industrial wood and removes fuels (lowers overall costs)
- Suitable for fuel treatments in stands with low industrial value
- Potential to produce fuel chips but larger number of impurities due to needles, branches and foliage
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- Stems are not delimbed
- Need for roadside processing for industrial wood portion
- Need to dispose of biomass at roadside
- High transportation costs due to lower density of stems (due to the crown)
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Felling heads with feedrollers
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- Multiple-tree handling
- High cutting productivity and lower cost, especially in small-diameter stands
- Potential to produce industrial wood and removes fuels (lowers overall costs)
- Industrial wood is already delimbed no need for roadside processing
- Large payloads in off-road and on-road transportation
- Low cost of forest haulage and road transportation
- Very versatile system – can be used for multiple purposes
- Produces high quality fuel chips for bioenergy
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- Biomass stays in the stand (CTL at stump) and will need to be removed in wildfire prone areas which adds an extra cost
- Produced quality of delmined stems might vary
- Not as efficient as a purpose build piece of equipment
- Needs a large component of industrial wood in order to be feasible
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