Excerpt from Ponderosa Pine Saplings Respond to Control of Spacing and Understory Vegetation Recent forest inventories indicate that about 5 million acres of commercial pon derosa pine forest land east of the Cascade Range in Washington and Oregon have a dense understory of suppressed trees.l On many additional acres, the overstory has been re moved, leaving dense thickets of 40 to 80-year-old, sapling-sized trees. Some man agers have chosen...