The Taylor Woods "Levels-of-Growing-Stock" study was established in 1962 to create a replicated ponderosa pine density experiment for the Southwest, making a valuable addition to research in the Fort Valley Experimental Forest. Basal area treatments ranged from 5-20 m2/ha (19-80 ft2/ac) when installed, designed as growing stock levels 30/40, 60, 80, 100, 120 and 150. Residual trees averaged only 12 cm DBH despite being 42 years old. These 0.3- to 0.5-ha (0.75- to 1.24-ac) plots, with three of each growing stock level, were revisited for maintenance on a decadal basis including a recent entry in 2002/3 (the fifth). Once trees averaged 25 cm (10 in), which varied among treatments, plots were maintained at their target basal area per the intent of growing stock studies; all plots were at or above that point in 2002 with the largest trees >50 cm (20 in). Results have shown clear and predictable patterns for height and diameter growth for southwestern ponderosa pine, not different than other parts of the species' range or other species. Lower density plots have shown consistently larger diameters and faster diameter and height growth on an individual tree basis. Standlevel basal area growth is higher at higher densities based on the higher number of trees per plot (and per ha). The density at which stands can achieve maximum basal area growth has varied progressively over the four decades. But beyond such traditional interpretations of density effects on tree and stand growth, the long-term patterns shown at Taylor Woods now provide valuable insights into tree vigor and insect resistance, understory development, fire behavior, ecological restoration and potential implications of regional land management choices in light of climate change.