College of Forestry

Trask Watershed Study

2012 Harvest

 

Summary of 2012 Harvest Practices for Trask River Watershed Study by ownership and watershed

After the intensive, pre-treatment phase of the study (2006 – 2011), harvest of all headwater basins slated for treatment began in 2012. Land ownership of these small basins included Federal (BLM), State (Oregon) and private corporations (Weyerhaeuser). The different harvest treatments were in alignment with Oregon Forest Practices Act and Oregon Forest Management Plan as well as economic evaluations by land owners. The linked Operations Documents below provide details of harvest planning and operations by landowner.

Harvest treatments overview:

  • Clearcut: A clearcut is a harvest where very few seedlings, saplings or poles remain. Two wildlife leave trees and 2 downed logs per acre are required and many tend to be located around the edge of the unit, including near the stream.  In the Oregon Coast Geo-region: no overstory retention required.
  • Modified Clearcut: Clearcuts are modified to leave residual green trees, snags, or other trees within the unit destined to become snags specifically for their biological or environmental values.  10m no touch buffer on perennial and seasonal streams.    
  • Retention Cut: Retention cuts are similar to partial cuts with similar amounts of basal area left on site.  Focus of future management will be on the new/young trees in the stand, rather than the residual trees. 10m no-touch buffer on perennial and seasonal streams.    
  • Thinning: Basal area retention target for thinning = 125 sq ft  +/- 5 sq ft per acre.  Non-fish bearing stream has 15m no touch riparian area each side.      

Operational considerations 

Some riparian buffers are wider than the prescription because of operational feasibility. In wet riparian area, leave trees around the streams of UM2 and UM3 were not harvested. In PH, the horizontal buffer width at the base of PH2 was wider than required because the proximity of the two perennial streams made it difficult to harvest the trees between the two buffers.  These “extra” or leave trees are then counted towards the green tree retention goals. 
 

History of forest disturbances: 

All of this area burned in 1933 in the Tillamook fire, again in 1939 in the Saddle Mountain fire and some of the area reburned in  1951 in the North Fork/Elkhorn fires. At the time of harvest in 2012, forest age was generally 55-60 yrs old. Some areas of the PH basin had been partially thinned in 1996.  For more details, see Contextual Analysis document.

 

Oregon Department of Forestry Ownership

  • PH1: Mixture of Modified and Retention clearcuts, but predominantly Retention.  Primarily Douglas-fir and red alder.  Plan was for approximately 90% cable and 10% ground-based (tractor) logging. Slash piles burned spring of 2013. Helicopter herbicide spray in autumn 2013.  Replanted with mix of 59% Douglas-fir, 32% Western hemlock, 7% Noble fir and 2% Western red cedar in winter of 2014.
  • PH2: Modified clearcut.  Primarily Douglas-fir and red alder. Plan was for approximately 90% cable and 10% ground-based (tractor) logging.  Slash piles burned spring of 2013. Helicopter herbicide spray for autumn 2013. Replanted with mix of 59% Douglas-fir, 32% Western hemlock, 7% Noble fir and 2% Western red cedar in winter of 2014.
  • PH4: Modified clearcut.  Primarily Douglas-fir and red alder, stand age 65 yr. Burned in 1933 Tillamook, 1939 Saddle Mountain fires, but only about 2 ha burned in 1951 North Fork/Elkhorn fires. Plan was for approximately 90% cable and 10% ground-based (tractor) logging. Slash piles burned spring of 2013. Helicopter herbicide spray for autumn 2013. Replanted with mix of 59% Douglas-fir, 32% Western hemlock, 7% Noble fir and 2% Western red cedar in winter of 2014.


For more details on areas under state ownership, click the links below:

Riparian Management Prescriptions Used on State Forests Sites in the Trask Watershed Study

Letter from State of Oregon Board of Forestry
 

Weyerhaeuser Ownership

  • UM2: Clearcut Harvest: 59% hand-cut with high lead cable, 41% ground-based machine.  Leave trees along lower channel below lower road and above upper spur road, areas too wet for machinery (alders remained in area approximately 8 m wide x 30 m). Slash piles burned November 2012. Herbicide applied September 2012, and trees replanted March 2013.  
  • UM3: Clearcut, with leave trees along lower stream channel and above road in middle of unit, areas too wet for machinery (approximately 14 m wide x 50 m).  Harvest: 20% hand-cut with high lead cable, 80% ground-based machine. Slash piles burned November 2012.  Herbicide applied September 2012, and trees replanted March 2013.  
  • GS3: Clearcut Harvest: 79% hand-cut with high lead cable, 21% ground-based machine. Leave trees were located away from stream, along NW lower edge of unit and NE upper section of unit. Slash piles burned November 2012. Herbicide applied autumn 2013, and trees replanted winter 2014.  
  • GS4: Clearcut, No leave trees in upper channel, but 55 m of lower end of habitat reach in adjacent stream buffer for medium sized stream. Harvest: 69% hand-cut with high lead cable, 31% ground-based machine. Slash piles burned November 2012. Herbicide applied autumn 2013, and trees replanted winter 2014. 

For more details on areas under private ownership, click the link below:

Private Forest Rules in Effect When the Trask Study Area Was Harvested in 2012 and How The Rules Were Applied in the Study Area
 

Bureau of Land Management Ownership

GS2: Pre-harvest conditions were a homogenous stand of 55 year old Douglas fir. The harvest was primarily a thinning operation for the Douglas-fir, retaining large trees, and all western hemlock and western red cedar in the understory. A total of 21.5 ha were harvested, 17% ground based and 83% helicopter logging. No piling or burning of slash occurred, and since this was a thinning operation, no replanting.