Patch Harvest
Definition
Management technique in pole staged or older stand using harvest removing trees in area with width equal to 0.3-2 tree stand heights. Maximum patch size opening: 0.5 ha (≈70 m diameter). Multi-pass treatment over time. Used to modify vertical structure, create openings to accelerate height growth of established seedlings, create micro-habitat for natural regeneration, create coarse woody debris. Patch harvests can be various shapes to create different shade conditions for changing species composition at shade tolerance level.
Eligibility Criteria
- Remaining stands: minimum average 30% live crown ratio
- >75% of stand is pole staged or older
- Stands normally well rooted and wind firm with little existing wind throw (unless managed primarily for acceleration of height growth of tolerant planted seedlings)
- Residual stand retained for period prescribed in management plan until management objective achieved (for natural regeneration: normally minimum 5 years following treatment and until patch cut areas adequately stocked; other objectives may require much longer periods with sequence of incremental cuts)
Guidelines and Assessment Procedures
- Extraction methods promoting scarification encouraged when desirable regeneration not present; goal of creating up to maximum 2500 micro-sites/ha adequately prepared and evenly distributed throughout patch
- Minimize damage; maximum 5% damaged crop trees
- Excluding legacy trees, snags, cavity trees: all merchantable wood removed, placed for extraction, and/or piled to create wildlife habitat
- Patch cut size prescribed in management plan
- Residual stand appears wind firm
- Initial patch cuts distributed as uniformly as possible throughout stand
- Target: injured trees, trees with reduced live crown ratios, less wind firm trees, areas with advanced regeneration
- Slash broadcast throughout harvest patch unless another treatment prescribed