Successful Maryland White Pine—Yellow-Poplar Plantation its Response to Thinning

Though not commonly grown together, a mixed plantation of 85 percent white pine and 15 percent yellow-poplar, established in 1912 on Baltimore, Md., watershed lands, has proved eminently successful. Portions of the stand were thinned at 25 years, reducing the number of stems from 776 to 300, 150, or 110 per acre. While 25 years later the biggest trees occurred in the heavier thinnings, the lightest thinning tried, equivalent to a 12-foot spacing, resulted in (1) the largest net increments in board-foot and cubic-foot volumes, (2) the greatest total board-foot volume at a stand age of 50 years, and (3) no epicormic branching of yellow-poplars such as temporarily developed in the wider spacings.