Development of Scots pine stands after first biomass thinning with implications on management profitability over rotation

Abstract

The aim of this study was to investigate the profitability of management regimes including both early biomass thinning (leaving 4000 stems/ha and using systematic boom-corridor thinning) and conventional production of pulp and timber. Empirical data obtained from five dense (11,000–20,000 stems/ha) naturally regenerated Scots pine experimental plots in which pre-commercial thinning (PCT) to 2500 stems/ha and control treatments (no PCT) were originally applied were used to initiate simulations. Biomass thinning was simulated at mean heights 6–7 m (BIO1) and 8–9 m (BIO2) in control plots. Land expectation values (LEVs) were calculated (3% interest rate), after simulating stands development to final harvest. Given the targeted stand stem density, 36–67 oven dry tons/ha were harvested in the simulations. Compared with PCT, both BIO regimes resulted in a somewhat lower average tree size in all subsequent harvest operations but a higher LEV in four of the five stands, if thinning was integrated with bundling. Higher LEVs (on average 27%) were achieved when BIO2 was applied compared to BIO1. Consequently, high biomass removal from dense Scots pine stands early in rotation periods might provide substantial economic benefits for forest owners, but appropriate general decision tools are needed to maximize profit.

Keywords:

• profitability
• pre-commercial thinning
• biomass thinning
• Scots pine
• natural regeneration

Acknowledgment

We are grateful to Sees editing for editorial assistance and to D.Sc. Anssi Ahtikoski for valuable comments regarding the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was funded by the Swedish Energy Agency and by the Kempe and Brattås foundations.