Ground-Based Primary Transport

1. Ground-Based Primary Transport TOPICS: Conventional ground skidding equipment Mechanical felling, tree processing & forwarding equipment & systems Management alternatives for soil compaction Operational planning & principles in designing skid trail systems

2. Ground-Based Primary Transport COURSE LEARNING OBJECTIVES: Harvesting process terminology; Capabilities & limitations of equipment & systems in a range of different silviculture systems Select/match ground-based equipment/ systems to different operating environments – considering equipment limitations, economics, environmental impact & social factors

3. Ground-Based Primary Transport ASSIGNMENT (Due Monday, Oct. 11 @ 11:00 AM Review SLC Video #850 (32 minutes) on Soil Compaction on Forest Lands Review SLC Video #903 (27 minutes) on Designated Skid Trails Submit a written summary of five alternatives for managing soil compaction

4. Ground-Based Primary Transport CONVENTIONAL GROUND SKIDDING ALTERNATIVES: Animals Track Skidders - Rigid Track - Flexible Track Rubber Tire Skidders - Line skidders - Grapple skidders Excavator Forwarder (shovel logging or hoe chucking) Clambunk Skidders Forwarders

5. Ground-Based Primary Transport GENERAL CHARACTERISTICS (ALL EQUIPMENT/SYSTEMS): • Lower productivity & lower logging costs than cable systems • Soil disturbance/compaction is a more significant concern with ground-based logging systems • Several excellent planning and management alternatives are available for controlling soil disturbance/compaction • Some equipment is best matched with thinning; others for clearcutting; others for both • Downhill transport is preferred • Terrain limits are generally: Downhill <35% Uphill < 20% Sidehill <20% • Economic maximum transport distances range from 500 to 2000 feet (downhill). Uphill transport is approx. half of downhill distance.

6. Horse Logging • Animal weights: 1,500–2,000 lbs • 800 – 1500 lbs payloads • < 25% downhill slope • 500 ft. max. skidding distance • Low productivity (2-3 MBF/day) • Approx. average skidding cost: $50/MBF (all ground-based systems) • Niche applications

9. Rigid-Track Skidders (Crawler Tractors) • Uniform ground contact only on even surfaces • Rear or elevated drive wheel • Loaded weight distribution (level surface): 80/20 • Equipment weight: 30 – 50 K lbs • 70 – 200 horsepower • < 40% downhill slope • 600 ft. max. skidding distance

10. Rigid-Track Skidders (Crawler Tractor) • Clearcut and partial cut applications • Equipment versatility • Average productivity (clearcut with favorable conditions): 20 MBF/day

11. Flexible-Track Skidders (High Speed or LGP Track Skidder) • FMC transferred rights to KMC • Uniform ground contact on uneven surfaces • Front drive wheel • Independent torsion suspension • Loaded weight distribution (level surface: 60/40 • Equipment weight: 30 – 40 K lbs • Average of 200 horsepower • Faster travel speed than crawler tractor • < 50% downhill slope • 800 ft. max. skidding distance

13. Flexible-Track Skidders (High Speed or LGP Track Skidder) • Clearcut and partial cut applications • Low ground pressure applications • Higher equipment purchase cost and maintenance cost • Average productivity similar to crawler tractor

14. Rubber Tire Skidder • All-wheel drive • Articulated steering (hinged in the center for steering) • Loaded weight distribution (level surface): 80/20 • Equipment weight: 20 – 35 K lbs • 100 – 200 horsepower • Travel speed similar to flexible track skidder • < 30% downhill slope • 600 ft. max. skidding distance

15. Rubber Tire Skidder • Line Skidders

16. Rubber Tire Skidder • Grapple Skidders (log or bunching) • Often matched with a feller- buncher in a whole tree skidding system

17. Rubber Tire Skidder • Lower payload capacity • Lower equipment purchase cost • Clearcut and partial cut applications • Potential for higher damage in thinnings than track skidder

18. Rubber Tire Skidder • Wide Tire Skidders (average width of 32” vs. 43”-50”) • Better “flotation” on low-strength soils • Lower tire sinkage & rolling resistance • Traction problems on wet steep slopes with logging slash

19. Excavator Forwarder (Shovel Logging or Hoe Chucking) • Modified hydraulic log loader • < 20% downhill (non self-leveling) • 400 ft. max. swing distance • High productivity (e.g.80 MBF/day) • Low ground impact in favorable operating conditions • Clearcut operations preferred • Serpentine or bunching patterns of operation

20. Excavator Forwarder (Shovel Logging or Hoe Chucking) Serpentine Forwarding Pattern Bunching Pattern with a Skidder Swing

21. Excavator Forwarder (Shovel Logging or Hoe Chucking) Hydraulic Log Loader with Winches • Steep slope cable yarding • Preferred yarding distances <400 ft. (max. 800 ft.) • Equipment versatility • Short cable yarding distance applications

22. Clambunk Skidders • Articulated chasis • Integral grapple arm and Inverted bunk grapple • Bogie wheels: Tandem axles driven by a single differential (lower ground pressure than single axles); often used with half-tracks for better traction

23. Clambunk Skidders • Matched with a feller-buncher and whole tree skidding system • High payloads (15 tons) • 1500 ft. max. skidding distance • <30% downhill slope • Clearcut operations – natural or plantation forests • Consider road impacts

24. Forwarders • Articulated chasis • Hydraulic loading grapple • Bogie wheels • 5 to 19 ton payload range • Short logs

25. Forwarders • Matched with a single-grip harvester and a CTL system • 2000 ft. max. skidding distance • < 30% ground slope • Thinning and fuels reduction applications

26. Ground-Based Primary Transport The actual equipment performance, productivity and costs, and soil impacts depends on site-specific conditions….. ….Logging mechanics consideration of factors including grade resistance (or assistance), skidding resistance, rolling resistance, soil strength and traction