Technodiversity Glossary

When trees are cross-cut at the felling site, the logs must be pre-skidded to the trail separately. This is only rational when the weight of the tree length is too high. For example, the basic log can be separated from the rest of the stem before pre-skidding.     

Functiogram:

• low weights, lower damage in the stand

• low productivity

• Small scale forestry
• simple, light machines

Economic suitability:

Minutes per cycle

Example:

• machine costs without personal costs: 60,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 2
• in total: 130,00 Euro/h
• regression line time per tree
  • b₀ = 4,0
  • b₁ (log volume) =  2,0
  • b₂ (skidding distance) = 0,1

Ecological suitability

Ecograms 

Social suitability:

• S-class: no contact with forest road -> S5
• E-class: simple machine work, heavy and dangerous -> E3

see SP-x1-x2 delimbing

Processor (or harvester) standing on skid road processing the full tree that is laying down in reach of feeding device. The processing includes measuring, forecasting dimension, suggesting assortments, delimbing and cross-cutting. 

Functiogram

Advantages

• High productivity, low price (if fully utilized)
• Low danger, low ergonomic injuries

• Good for coniferous trees with straight stems
• Limited with bigger, crooked or broadleaves trees

• On accessible skidroads
• Coniferous trees, younger broadleaves trees
• Distance of skid roads > 2x reach of crane

Economic suitability

Example:

• machine costs without personal costs: 160,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 1
• in total: 195,00 Euro/h
• regression line minutes per tree
  • b₀ = 0,5
  • b₁ (tree volume) = 2,0

Ecological suitability

Ecograms 

Social suitability

• S-class: no contact with forest road -> S5
• E-class: automatic machine work, moderate -> E5

Functiogram

• very fast loading and unloading
• no need to have an assistant to hook the loads
• no need for the operator to leave the cab
• by chains also possible on softer soils

• trees need to be pre-bunched for the system to be efficient
• smaller payload than for a clambunk or a forwarder
• high speed and many repetitive cycles are heavy on the operator

• plantation forestry (grapple-skidders on pre-bunched trees)

Economic suitability

Example:

• machine costs without personal costs: 80,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 1
• in total: 115,00 Euro/h
• regression line minutes per tree
  • b₀ = 2,5
  • b₁ (tree volume) = 1,0
  • b₂ (skidding distance) = 0,01 

Ecological suitability

Ecograms

Social suitability:

• S-class: unloading full trees on the road -> S3
• E-class: advanced machine work, moderate -> E4

Functiogram:

• It does not require to process the trees in the forest
• simple machine and procedure
• it can drag long loads
• high speed

• It requires large landings or a separate loader
  
• needs skid trail in dense stands and or on steep terrain
  
• relatively small payload
  
• high speed and many repetitive cycles are heavy on the operator
  
• aggressive on the soil (esp. crawlers in steep terrain)
  
• operator needs to leave the cab and re-enter the cab twice per cycle, unless an assistant is available to do so (uncomfortable)
  

• mountain operations
• when we are not able to run a harvester-forwarder system and want to mechanize at roadside by processor (or chipper)

Economic suitability

Example:

• machine costs without personal costs: 40,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 2
• in total: 110,00 Euro/h
• regression line minutes per tree
  • b₀ = 5
  • b₁ (tree volume) = 1
  • B2 (skidding distance) = 0,01

Ecological suitability

Ecograms

Social suitability:

• S-class: unloading full trees on the road -> S3
• E-class: simple machine work, heavy and dangerous -> E3

graph from Ecotrac study and Rien's lesson (re-conduce  everything to tree size m3 on the x-axis, then different lines for different distances and maybe one graph for small skidder and one for large skidder)

• Much reduced friction, soil disturbance and contamination
• larger loads can be assembled, than it would be possible with a cable or grapple skidder

• Large machine, very heavy and expensive
• limited maneuverability, clumsy

• Plantation forestry
• Boreal forests on solid ground
• Whenever long assortments need to be produced, and logs cannot be cut short (conversion kits for forwarders and skidder available)
• Costs per m³ depending on tree volume

Economic suitability

Example:

• machine costs without personal costs: 90,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 1
• in total: 125,00 Euro/h
• regression line time per tree
  • b₀ = 0,0
  • b₁ (load volume) = 2,0
  • b2 (skidding distance) = 0,01

Ecological suitability

Ecograms

Social suitability:

• S-class: unloading full trees on the road -> S3
• E-class: advanced machine work, moderate -> E4 

Full trees that are laid down alongside the trail are chipped by a self-propelled chipper or a tractor powered chipper with terrain capability. Chips are blown into an integral bin and then transferred to a chip shuttle (forwarder-based) or into a bin trailer, towed by the same tractor or by an accompanying tractor.

Functiogram

• Trees are compacted into chips as early as possible to accrue all advantages of bulk density reduction and "fluidization"
• Minimum tree handling
• Minimum contamination

• Needs suitable terrain conditions
• Expansive machinery
• Potential for interaction delays in the chipper-shuttle interface
• Temptation to use the integral bin as a chip-forwarder (only on a very short distances)

• Danish forestry – thinning there is very effective

Economic suitability

Example:

• machine costs without personal costs: 120,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 2
• in total: 190,00 Euro/h
• regression line minutes per tree
  • b₀ = 0,2
  • b₁ (tree volume) = 2,0
  • b₂ (skidding distance) = 0,03

Ecological suitability

Ecograms

Social suitability:

• S-class: no contact with forest road -> S5
• E-class: advanced machine work, moderate -> E4

Check Waterford studies

see SP-x2-x3 cross-cutting

Functiogram

• compared with full trees you can build bigger loads (about 30%)
• compared with skidder, the driver can remain in the cabin
• high productivity    

• Large machine, very heavy and expensive
• limited maneuverability, clumsy

• Traditional extraction method when crosscutting should not be done before reaching the forest road (or the customer)
• high extraction volume like clear-cuts or wind-throws

Economic suitability

Example:

• machine costs without personal costs: 90,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 1
• in total: 125,00 Euro/h
• regression line minutes per tree
  • b₀ = 0,5
  • b₁ (tree volume) = 2,0
  • b₂ (skidding distance) = 0,01
  • 
    

Ecological suitability

Ecograms

Social suitability

• S-class: unloading tree length on the road -> S3
• E-class: advanced machine work, moderate -> E4

Logging arch study for farm tractors - Merlo study etc.

Tree lengths that are pre-skidded to the trail are skidded to the forest road. This includes: setting chokers on several tree-lengths to optimize the load, skidding them to forest road, storing them alongside road or a landing.

Functiogram

• High productivity because of high mass/load
• Versatile machine, esp. if farm-tractor based (farm work, snow work, transportation etc.)
• Relatively cheap machine
• Independent relocation if road-legal

• Damages in remaining stand at curves
• Damage to ground (rutting)
• Damage and dirt on logs

• Extraction method when crosscutting should not be done before reaching the forest road (or the customer)
• Very common method in broadleaved trees

Economic suitability

Minutes per cycle

Example:

• machine costs without personal costs: 40,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 2
• in total: 110,00 Euro/h
• regression line minutes per tree
  • b₀ = 3,0
  • b₁ (tree volume) = 1,0
  • b₂ (skidding distance) = 0,01

Ecological suitability

Ecograms 

Social suitability

• S-class: unloading tree length on the road -> S3
  
• E-class: simple machine work, heavy and dangerous -> E3