Technodiversity Glossary

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

Pre-skidding of full trees from the felling site to the strip road with a winch that is mounted or attached to a tractor. 

Functiogram

Advantages

• extraction over long distance without driving on the ground 
• extracting in steep terrain (uphill)
• bringing trees to a site where machines for delimbing and cross-cutting can operate

Limitations, threshold

• distance limited by the length of the cable, often more than 100 m
• distance limited by the weight of the cable that must be pulled by the worker, so on flat terrain not more than 50 m, downhill wider distances are possible
• cable cannot be pulled uphill, therefore no downhill extraction over longer distance 

Main use

• in stands where fully mechanized methods are not applicable due to ground conditions, tree species (large broadleaf trees, e.g.)
• with wider distance of trails, where trees must be pulled into the reach of the crane of a machine
• in combination with extraction by means of a tractor 

Economic suitability

Winching performance depends on many factors, but mostly on extraction distance and tree size.

However, extraction distance and tree size have the strongest effect on cycle time, productivity and pre-skidding cost.

• When pre-skidding distance increases from 20 to 60 m (i.e. triples), then productivity decreases between 40 and 70% and pre-skidding cost increases up to 2.5 times. The effect of pre-skidding distance is stronger with smaller tree volumes.
• When tree volume increases from 0.1 to 1 m³ (i.e. factor 10), then productivity increases between 50 and 180% and pre-skidding cost  decreases between 33 and 66%. The effect of tree volume is stronger on shorter distances.

• machine costs without personal costs: 10,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 2
• in total: 80,00 Euro/h
• regression line minutes per tree
  • b₀ = 1
  • b₁ (depending on tree volume) = 3
  • b₂ (depending on pre-skidding distance) = 0,15

Since winch pre-skidding is extremely sensitive to distance, it should be used on very short distances, only. If tree volume is large enough, then one can obtain acceptable results also on medium distances, up to 50 m.

Ecological suitability

Ecograms

Social suitability

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

Dekking J. 1984 Goliat, a small tractor with tracks. IEA/FE/CPC7 Report, 17 pp.

Dunnigan J. 1993 Braided Kevlar^TM Cable: Trials in Skidding Wood With an ATV. Field Note FN-022. FERIC. Pointe Claire, Quebec, Canada.

Ewing R. 2001 Use of a portable capstan winch and associated hand tools in manual thinning. FERIC Advantage Reports, 28: 4 p.

Ewing R. 2003 Harvesting riparian zones using cable skidders equipped with Spectra synthetic-fibre mainlines. FERIC Advantage Reports, 20: 6 p.

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

Hill S. 1991 D4H tractor and towed arch in radiate clearfell. LIRA Report 16, 8. 4 p.

Horvat D, Spinelli R, Šušnjar M. 2005 Resistance coefficients on ground-based winching of timber. Croatian Journal of Forest Engineering 30: 3-11

Leek N. 1976 Bunching with Radiotir 740 in thinnings. Nederlands Bosbouw Tijdschrift 48: 151-157.

Magagnotti N., Spinelli R. 2012 Replacing steel cable with synthetic rope to reduce operator workload during log winching operations. Small Scale Forestry 11: 223-236.

Picchio R., Magagnotti N., Sirna A., Spinelli R. 2012 Improved winching technique to reduce logging damage. Ecological Engineering 47: 83-86.

Prebble R. 1986. Evaluation of the Logquip smart arch. LIRA Report 11, 5. 4 p.

Pritchard N. 1986. The Logquip smart arch for small crawler tractors. LIRA Report 8. 4 p.

Ryans M. 1980 Evaluation of the Agri-Winch: a farm tractor-mounted logging winch. FERIC Tech. Rep. TR41. 18 p.

Spinelli R, Magagnotti N 2012 Wood extraction with farm tractor and sulky: estimating productivity, cost and energy consumption. Small-scale Forestry 11: 73-85.

TDB 2002 ATC timber sulky. Information Note ODW 9.04, Ae Village, UK. 5 p.

 Turner T., Huyler N. Bousquet D. 1988 Farm Tractor Skidding Costs in Relation to Profitability of a Fuelwood Harvesting System. Nort.h J Appli For 5: 207-210

Vaughan L. 1988 Thinning with small crawler tractors. LIRA Report 13, 26. 6 p.

Zeĉić Z., Krpan A., Vukuŝić S. 2005 Productivity of Holder 870 tractor with double drum winch Igland 4002 in thinning beech stands. Croatian J For Eng 26: 49-56.

Felled trees are pulled to a trail by means of a tractor winch and collected; when some full trees are collected, the tractor extracts them to the forest road and unloads alongside the road.

Functiogram

Advantages

• due to the cable, the area from which full trees can be extracted, is large
• capable for steep terrain (pre-skidding uphill)

Limitations. thresholds

• extraction length of the cable limited by the human power, maximum 50 m
• damage caused by the full trees

Main use

• small scale forestry with own tractors

Economic suitability

Example:

• machine costs without personal costs: 65,00 Euro/h
• personal costs per person: 35,00 Euro/h
• number of persons: 2
• in total: 135,00 Euro/h
• regression line minutes per tree
  • b₀ = 4,0
  • b₁ (tree volume) = 2,0
  • b₂ (skidding distance) = 0,005

Ecological suitability:

Ecograms

Social suitability:

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