Technodiversity Glossary

Cutting tree at the base with chainsaw and fell it in a predefined pattern.

Functiogram:

Advantages

• no need to relocate machines
  
• low investment
  
• accessibility to almost all terrain condition
  
• no need for strip roads (unless needed by extraction vehicles)
  
• no tree size limitation
  
• higher productivity than manual work
  

 Limitations, thresholds

• safety: motor-manual felling is very dangerous
  
• requires high skills
  
• tiresome, high strains
  

Main use

• thinning operations (pure selection)
  
• steep terrain
  
• broadleaf trees with higher dimensions
• wherever machine access is limited

• machine costs without personal costs: 4.00 Euro/h
• personal costs per person: 35.00 Euro/h
• number of persons involved: 1
• in total: 39.00 Euro/h
• regression formula: 
  • b_o = 8
  • b₁ = 15

Ecological suitability:

• Felling damage can occur when the forest stand is dense; depends on the education and skill of the forest worker
• Ecogram 

Social suitability:

• S-class: no work on forest roads -> S5
• E-class: motor-manual work, very heavy and dangerous -> E2

Anonymous (2007): Scope of best operation practice (bop). (unveröffentlicht). Hg. v. Forestry Solutions.

Engler, Benjamin (2011): Gestaltung von Arbeitsprozessen bei der Bewirtschaftung von Eukalyptusplantagen in Süd-China. Analyse gegenwärtiger Arbeitsverfahren und Modellierung eines höheren Mechanisierungsgrades in der Holzernte zur Beurteilung der ökonomischen Auswirkungen. Dissertation. Albert-Ludwigs-Universität Freiburg, Freiburg.

Advantages

• Very flexible, nearly every tree can be processed
• No dependency on skid roads
• Low investment cost
• Low relocation cost

• High need for skills with increasing stem volume
• Dangerous work
• Cost with low productivity
• Effort: heavy cardio-vascular workload
• Need to have at least another (or other 2 workers) at the worksite. Cannot work alone (legal obligation in some countries, in some certification schemes, too)

• Standard at sites with tree-length skidding
• Broad-leaved trees, tree volume too high for harvester or stand not accessible for harvester

• machine costs without personal costs: 4.00 Euro/h
  
• personal costs per person: 35.00 Euro/h
  
• number of persons involved: 1
  
• in total: 39.00 Euro/h
• regression formula
• • b₀ = 15
  • b₁  = 15

Ecological suitability:

• Ecogram 

Social suitability:

• S-class: no contact with forest road -> S5
• E-class: motor-manual work, very heavy and dangerous work -> E2 

Felling, delimbing and bucking to standard industrial logs or differentiated assortments directly in the stand

Functiogram:

 

• Letting nutrients and biomass in the stand
• No transport of waste
• Low investment
• Low relocation cost

• Dangerous work, ergonomic limitations
• Extreme danger at steep terrain
• Costs of processing
• High costs of pre-skidding (logs are not bunched/stacked - follows higher cost of forwarding)

• For lowering the mass of the logs in order to ease manual pre-skidding (animal, hand)

Economic suitability

Example:

• machine costs without personal costs: 4,0 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 1
• in total: 39,00 Euro/h
  • regression line time per tree
  • b₀ = 4,0
  • b₁ (tree volume) =  22,0

Ecological suitability:

• Ecogram 

Social suitability:

• S-class: no contact with forest road -> S5
• E-class: motor-manual work, very heavy and dangerous -> E2

If this is the only function, the machine is called feller. But a harvester can do the job as well.   

• it is a machine work if the working on site is dangerous
• taking the work apart from extremely danger site
• bunching tree into a suitable loads and/or laying down in a orderly pattern

• bringing the felling head to the felling site (skid roads or driving without the limitation on the ground)
• machine accessibility to the site (need a strip road, no pure selection)

• first cut in windthrows or on steep terrain
• biomass operation in thinning

Economic suitability:

Example

• machine costs without personal costs: 65,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 1
• in total: 100,00 Euro/h
• regression line time per tree
  • b0 = 2 min/tree
  • b1 = 0,5 min/m³

Ecological suitability:

Social suitability:

• S-class: work has no contact with forest roads, S5
• E-class: advanced machine work, E4

Schweier, J., Spinelli, R., Magagnotti, N., Becker, G. (2015) Mechanized coppice harvesting with new small-scale feller-bunchers: Results from harvesting trials with newly manufactured felling heads in Italy. Biomass and Bioenergy, 72, pp. 85-94. 

Spinelli, R., Cuchet, E., Roux, P. (2007) A new feller-buncher for harvesting energy wood: Results from a European test programme. Biomass and Bioenergy, 31 (4), pp. 205-210.

Spinelli R., Hartsough B., Owende P., Ward S. (2002) Productivity and cost of mechanized whole-tree harvesting of fast-growing eucalypt stands. International Journal of Forest Engineering 13, p. 49-60.

Cacot E. Chantier de St. Vitte sur Briance (87)- Abattage mecanisé des peuplements feuillus par une tête a guillotine. Paris: AFOCEL Flash Chantier CO68; 2004.

Hiesl P, Benjamin J. 2013. A multi-stem feller-buncher cycle-time model for partial harvest of small-diameter wood stands. IFJE 2013;24(2):101-108.

Visser R., Stampfer K. 2003 Tree lenght system evaluation of second thinning in a loblolly pine plantation. Southern Journal of Applied Forestry 27: 77-82

Trees are felled and delimbed with a harvester, but trees are not crosscut (generally with the intention of postponing bucking at a better facility in order to maximize value recovery)

Functiogram:

• Safer compared with motor-manual operations
• Faster compared with mechanized harvesting of short logs in clearcuts
• Possibility to work on ghost trails and increase distance between skid trails (where ghost trails are allowed)

• Tree-lengths are less maneuverable than short logs
• Higher potential for residual stand damage, esp. during subsequent extraction

• Plantation forestry, often associated with the use of centralized processing yards

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 = 1,0
  • b₁ (tree volume) = 1,0 

Ecological suitability:

Ecograms 

Social suitability:

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

• Harvester standing on skid road
• Gripping into stand to fell tree (or in front to open up new skid road)
• pre-skid full tree by lifting the crane
• processing in front of machine, storing along skid road 

Functiogram

• Very highly productive
• Good working site
• Very low damage in stand because of upright pre-skidding and cross-cutting directly at the skid road = before the first curve has to be taken

• Distance of skid
• Roads not more than 2x reach of crane
• Coniferous trees or younger broadleaved trees

• Standard method on sites, which are accessible for wheeled machines
• With  roads or with traction-line also in steep terrain

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) = 2,3

Ecological suitability:

Ecograms

Social suitability:

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

Brunberg T. 1997. Basic data for productivity norms for single-grip harvesters in thinning. The Forestry Research Institute of Sweden, Report 8/1997. 18 p. (In Swedish, English summary)

Brunberg T. 1995. Basic data for productivity norms for heavy-duty single-grip harvesters in final felling. The Forestry Research Institute of Sweden, Report 7/1995. 22 p. (In Swedish, English summary)

Emeyriat R., Picorit C., Reuling D., 1997. Perspectives of mechanised harvesting of maritime pine. Information Forèt, AFOCEL, Paris. Fiche 561, 6 p. (In French).

Glöde D. 1999. Single- and double-grip harvesters: productive measurements in final cutting of shelterwood. Journal of Forest Engineering 10 (2): 63-74.

Hǻnell B., Nordfjell T., Eliasson L. 2000. Productivity and costs in shelterwood harvesting. Scandinavian Journal of Forest Research 15 (5): 561-569.

Kärhä K., Rönkkö E., Gumse S. 2004. Productivity and cutting costs of thinning harvesters. International Journal of Forest Engineering 15 (2): 43-56.

Nakagawa M., Hamatsu J., Saitou T., Ishida H. 2007. Effects of tree size on productivity and time required for work elements in selective thinning by a harvester. International Journal of Forest Engineering 18 (2): 24-28.

Nurminen T., Korpunen H., Uusitalo J. 2006. Time consumption analysis of mechanized cut-to-length harvesting systems. Silva Fennica 40 (2): 335-363.

Purfürst F. 2007. Human influences on harvest operations. Proceedings of Austro 2007/FORMEC’07 “Meeting the Needs of Tomorrows’ Forests – New Development in Forest Engineering” October 7-11 2007, Vienna and Heiligenkreuz, Austria. 9 p.

Sirén M., Aaltio. 2003. Productivity and costs of thinning harvesters and harvester-forwarders. International Journal of Forest Engineering 14 (1): 39-48.

 Spinelli R., Magagnotti N., Nati C. 2009 Options for the mechanised processing of hardwood trees in Mediterranean forests. International Journal of Forest Engineering 20 (1): 39-44

Spinelli R., Owende P., Ward S. 2002. Productivity and cost of CTL harvesting of Eucalyptus globulus stands using excavator-based harvesters. Forest Products Journal 52 (1): 67-77.

 Spinelli, R., Hartsough, B., Magagnotti, N. (2010) Productivity standards for harvesters and processors in Italy. Forest Products Journal 60 (3), pp. 226-235.

• Combination of harvester and forwarder: forwarder with harvester head at the tip of the crane
• Working like harvester, but feeding logs directly into the basket until full, then forwarding and unloading

Functiogram

• 1 machine, 1 driver, 1 times moving  to the felling site
• No access for the harvester – 1 turn less on the skid road (but harvester is not important when followed by forwarder)
• Cleanest load - no contamination

• While processing is forwarder not productive, while transporting is the heavy and expensive harvester head unproductive
• Possible lower payload/tare ratio?

• Only in areas where there is few harvesting mass (like singular windthrows, beatle trees) so that machine can finish its job at the first access

Example:

• machine costs without personal costs: 250,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 1
• in total: 285,00 Euro/h
• regression line minutes per tree
  • b₀ = 0,5
  • b₁ (tree volume) = 2,3
  • b₂ (skidding distance) = 0,01

Ecological suitability:

Ecograms

Social suitability:

• S-class: unloading of short wood at forest road -> S4
• E-class: advanced machine work, moderate -> E4

One single machine cuts and  chips whole trees in one single passage. This system is applied to SRC plantations and the most popular units are based on powerful (≥300 Kw) foragers

Functiogram: 

• Harvesting is simple: one single pass
• High productivity 20-35 t/h
• The base unit can be used for other tasks than SRC harvesting

• Chips are wet and cannot be dried without an energy input (active drying) or losses (passive drying)
• Requires flat terrain, solid
• Requires that the crop is in orderly rows
• Rather inflexible for stem size

• Industrial SRC in ex-arable land

Economic suitability

Example:

• machine costs without personal costs: 250,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 2
• in total: 320,00 Euro/h
• regression line time per tree
  • b₀ = 0,2
  • b₁ (tree volume) = 1,0
  • b₂ (skidding distance) = 0,01

Ecological suitability:

Ecograms

Social suitability:

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

see SP-x1-x2 delimbing

After felling, trees are pre-skidded to a strip road using animals, and most commonly draught horses. Different breeds are available in different regions, but the most popular are heavy breeds like French Percherons, Belgian Ardennes, or Italian TPR.

Functiogram

Advantages

• Capacity to work in dense stands and narrow corridors, inaccessible to mechanical vehicles.
• Capacity to handle soft or steep terrain (provided extraction proceeds downhill).
• Very low soil and stand impacts, because the animal has neither the size nor the power of a machine, and therefore it can never resort to brute force against an obstacle, but it must rather use brains and technique.
• Safety for the operator, who can control the horse at a distance through voice commands.
• Comfort for the operator, who is spared noise, vibration, exhaust gases, heavy cable pulls and tiresome walks on uphill grades (since he can ride the horse if the walk is too hard).
• Competitive cost on intermediate pulls (between 50 and 100 m), which are too long for direct winching and too short for cost-effective cable yarding.

• The system is suitable for young trees only, as obtained from first and second thinnings, or to coppice harvesting operations. The size of older trees is generally too large for an animal to move them without preliminary delimbing and crosscutting
  
• Distance must not exceed 200 m. Best results are obtained on shorter distances, between 25 and 100 m.
• Extraction must proceed on flat terrain or downhill slopes, with a maximum gradient of 50%. Experienced animals and drivers can safely handle steep terrain.
• Draught animals can only work 5 to 6 hours a day.  Operators working longer hours generally keep two animals and rotate them.

Main use

• Animal pre-skidding is still competitive with other mechanized pre-skidding systems (winches, mini-skidders etc.), but it is rarely used in industrialized countries, where it remains a specialist niche. The reason is in the small numbers of horse loggers, ready to accept the constant commitment imposed by animal care.

Economic suitability

• system costs without personal costs: 10,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 1
• in total: 45,00 Euro/h
• cross-cutting if volume/tree exceeds 0,4 m³ 
• regression line minutes per log
  • b₀ = 3
  • b₁ (tree volume) = 10
  • b₂ (pre-skidding distance) = 0,025

Ecological suitability:

Ecogram 

Social suitability:

• S-class: no contact with forest road -> S5
• E-class: very heavy and dangerous manual work -> E1

Baigent C. 1984. Clydesdale logging. LIRO Technical Release 6, 4 pp.

De Paul M., Bailly M. 2005. À propos de la pression exercée par les pneus, chenilles et sabots. Forêt Wallonne 78: 21-33.

De Paul M., Lombaerde F., Jourez B. 2006. Approche économique du cheval en forêt. Forêt Wallonne 81: 15-25.

Harstela P., Tervo L. 1981 Bunching of timber by winches and horse. Folia Forestalia 466, 20 pp. In Finnish.

Hedman L. 1987. Tools and equipment for horse logging. Small Scale For 1: 10-17.

Hedman L. 1988. Skidding with horse to strip road. Small Scale For 2: 15-19.

Leinert S. 1979 Einsatz veraltungseingener pferde beim vorrücken von schwachholz. Forsttechnische Informationen 1: 4-6.

Magagnotti N., Spinelli R. 2011 Integrating animal and mechanical operations in protected areas. Croatian Journal of Forest Engineering 32: 489-499.

Magagnotti N., Spinelli R. 2011 Financial and energy cost of low-impact wood extraction in environmentally sensitive areas. Ecological Engineering 37: 601-606.

McNamara D, Kaufman J. 1985. Can horses compete with tractors? State of California, For. Dept., Sacramento, CA. For. Note 95, 7 p.

Pynn L. 1991. Logging with horse power. Can Geogr 3: 31-35.

Shresta S, Rummer R, Dubois M. 2005 Utilization and cost of log production from animal logging operations. Int J For Eng 16: 167-180

Shresta S, Lanford B., Rummer R, Dubois M. 2008 Soil disturbances from horse/mule logging operations coupled with machines in the Southern United States. Int J For Eng 19: 17-23

Schroll E. (Editor) 2008 Holzrücken mit pferden – Handbuch für die waldarbeit mit pferden. Starke Pferde Verlag, Lemgo, Germany. In German.

Snoeck B. 2000. Ces chevaux « qui traînent au bois ».  Forêt Wallonne 46: 12-23.

Thérer Y. 2006. Situation du débardage au cheval en Région Wallonne, enquête auprès de débardeurs. Forêt Wallonne 82: 18-27.

Toms C., Dubois M., Bliss J., Wilhoit J., Rummer B. 2001 A survey of animal-powered logging in Alabama. South J Appl For 25: 17-24