Heavy thinning of ponderosa pine stands: An Arizona case study

Growth and structural changes in a mosaic of even-aged ponderosa pine (Pinu s ponderosa) stands were studied for 25 years to determine the long-term im pacts of a heavy thinning treatment to a basal-area level of 25 ft(2)/acre. Basal area and volume growth of these stands has increased since thinning and likely will continue to increase as the residual trees increase in size . Furthermore, future stand integrity should be maintained at relatively lo w-density levels. It is unlikely, however, that timber production could be sustained at this level. A more plausible scenario is to manage the watersh ed for other resource values available from ponderosa pine stands.