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Cutblock Design Strategies

Openings Parallel to Prevailing Winds
  • Reducing the length of the opening parallel to wind direction reduces wind loading on trees at the downwind boundary, thereby reducing treatment risk.
  • While results vary for different studies, to maintain a sheltering effect, the opening length should be less than 5 tree lengths.
Openings Perpendicular to Prevailing Winds
  • Reducing the width of the opening perpendicular (at right angles) to wind direction also affects wind loading on trees at the downwind boundary.
  • A sheltering effect occurs for openings narrower than 1.5 tree lengths.
  • Between 1.5 and 4 tree lengths wide, there is a funnelling effect.
 

 

Openings parallel to prevailing winds. Show Larger Image

Openings perpendicular to prevailing winds. Show Larger Image
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