Resumen

ALZUGARAY, PATRICIO; HAASE, DIANE  y  ROSE, ROBIN. Effects of preplanting root volume and fertilization rate on field performance of 1+1 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings . Bosque (Valdivia) [online]. 2004, vol.25, n.2, pp. 17-33. ISSN 0717-9200.  doi: 10.4067/S0717-92002004000200003.

To determine the combined effects of the preplanting root volume and fertilization rate on seedling field performance, Douglas-fir 1+1 seedlings, grown using standard practices at the Weyerhaeuser Aurora nursery (Oregon, USA), were sorted into four root-volume categories (8-13, 14-17, 18-22, and 23-35 cm3), and planted in a recent clearcut in Oregon State University’s McDonald-Dunn Research Forest on January 19, 2000 using a complete randomized block design with five replicates in a factorial treatment arrangement. A Simplot Polyon^® fertilizer mixture, containing equal parts of three fertilizers with different release rates (3-4, 5-6, and 8-9 months) and similar NPK concentrations (19-6-12) was applied at the time of planting in the bottom of the planting hole to each root-volume category at five rates: 0 (unfertilized control), 15, 30, 45 and 60 g per seedling. After two growing seasons in the field, there was no interaction between root volume and fertilization rate for seedling growth and survival. Seedlings with a larger preplanting root volume had greater survival and growth than seedlings with a smaller root volume. There was a significant reduction in seedling survival and growth with increasing fertilization rate.

Palabras clave : reforestation; seedling quality; root-volume; fertilization; Douglas-fir.