Investigation of Douglas-fir provenance test in North-Western Bulgaria at the age of 24 years
K. Petkova, M. Georgieva, M. Uzunovhttps://doi.org/10.17221/12/2014-JFSCitation:Petkova K., Georgieva M., Uzunov M. (2014): Investigation of Douglas-fir provenance test in North-Western Bulgaria at the age of 24 years. J. For. Sci., 60: 288-296.
A comparative analysis of growth rate and health condition of 54 Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) provenances was conducted at the age of 24 years. The provenance test was established in 1990 with 3-year-old (3+0) seedlings planted in a 2 × 2 m plot design and two replications. The provenances which were studied originated from North America and were separated into coastal, continental and Western Cascade groups. In 2011 the growth rate was studied in terms of height, diameter at breast height and stem volume. The health condition was assessed by the evidence of symptoms and degree of defoliation caused by the fungi Phaeocryptopus gaeumannii (Rohde) Petrak and Rhabdocline pseudotsugae (Syd.). The provenances Newhalem, Darrington, Idanha and Bremerton were characterized by the most rapid growth, highest productivity and lower susceptibility to both fungal pathogens. These Douglas-fir provenances were recommended for future afforestation in Bulgaria. Ten continental provenances should be excluded from future afforestation because of their lowest growth rate and productivity and high susceptibility to P. gaeumannii and R. pseudotsugae.Keywords:
adaptation; Phaeocryptopus gaeumannii; provenances; Pseudotsuga menziesii; Rhabdocline pseudotsugae;tree growth