Basal area growth curves for Pinus patula in two areas of the Calamuchita Valley, Cordoba, Argentina

This study was carried out in the Calamuchita Valley, in West Central Cordo ba, Argentina. Two stands of Pinus patula were chosen, one in each of two d ifferent areas: Yacanto de Calamuchita and Rio de los Sauces. The objectives of the study were: 1. to develop basal area (BA) mean annual increment (AI) and current annual increment (CAI) curves for P. patula in two areas of the Valle de Calamuch ita; 2. to estimate the timing of intermediate and final cuts in P. patula plant ations; 3. to evaluate P. patula BA growth rate vs, other pine species that grow in the region; and 4. to identify the best growing species for each area. Thirty trees were randomly selected in each stand. An increment core was ta ken from each sampled tree from bark to bark through the pith. Growth rings were measured and BA-MAI and BA-CAI were calculated. Growth curves were fi tted for each stand and intersection points between the MAI and CAI curves were found. Regression analysis was performed for BA-CAI vs. time up to the age of 10 years in both areas. P. patula performance was compared to that of P. elliottii, P. taeda and P. radiata growing in the same areas. It is concluded that: 1. The proper time for the first commercial thinning is about 10-12 years, just before the BA-CAI curve declines. 2. The biological rotation age is expected to occur no sooner than Year 17 in this region. 3. P. patula can perform better than P. elliottii, P. taeda and P. radiata during the first 10 years, depending on site quality and seed genetic quali ty. (C) 1999 Elsevier Science B.V. All rights reserved.