Since the early 1980’s, 1550 ha of high-density jack pine (Pinus banksiana) plantations have been established annually in Northern Lower Michigan to serve as habitat for the federally-endangered Kirtland’s warbler (Setophaga kirtlandii). Because these plantations do not produce merchantable sawlogs by their planned 50-year harvest age, I investigated the potential to implement reduced rotation lengths in these stands to produce alternative wood products, namely biomass and pulpwood. I used space-for-time substitution to assess biomass and volume accrual over time, sampling a total of 37 warbler plantations ranging from 7 to 52 years of age. I also destructively sampled 26 living and 8 dead stems to develop allometric equations specific to jack pine grown in these plantations. Potential maximum biomass was estimated to be ~71 Mg ha-1 and potential maximum volume was estimated to be ~71 m3 ha-1. The predicted optimal rotation age for biomass was 20 years and the predicted optimal rotation age for volume was 28 years. I calculated and compared the total land area required for management under these rotation scenarios to continue establishing 1550 ha of habitat annually. Management on the current 50-year cycle requires ~77,500 ha. Management for volume would reduce this to ~43,400 ha and management for biomass would require ~31,000 ha. My results suggest that rotation lengths in these plantations could be significantly reduced, allowing for reductions in the total land area dedicated to warbler habitat, allowing for management diversification at the landscape level.
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