Growing stock inventory on industrial and nonindustrial private forest (NIPF) lands in eastern Oregon has declined over the past 20 yr, as harvesting and mortality losses to insects and disease have outpaced growth. Over the same time period, harvest rates on private lands have varied, with no distinct trend to the variation. In the most recent survey (1999), industrial and NIPF inventories differed by less than 8% (1.786 billion ft3 versus 1.655 billion ft3), while the NIPF timberland base was only two-thirds of the industrial base (1.105 million ac versus 1.603 million ac). This study employs recent inventories and even-flow and market-based harvest simulators to develop projections of future harvest potentials. For industrial lands, even-flow and market-based projections of future harvest potential over the next 50 yr are approximately half of average harvests over the past 40 yr. For NIPF lands the even-flow projection is 20% higher than the historical harvest average, while the market-based projection indicates potential for a substantial but short-lived increase in near-term harvest. Inventories on industrial lands rise under both projections, while NIPF inventories remain fairly stable. Continued loss of land from NIPF ownerships to other owners and uses has limited influence on the market-based NIPF harvest projection until after 2050. A simulated policy of expanded riparian protection zones reduces harvest on both ownerships roughly in proportion to the area removed from the harvestable land base. A simulated requirement to retain 30% more residual volume in partially cut stands reduces harvest by 5% on combined private ownerships and increases total inventory by 13% after 50 yr.