The distribution of pine mistletoe (Viscum album ssp. austriacum) in Scots pine (Pinus sylvestris) forests: from stand to tree level

This paper reports and discusses the distribution of pine mistletoe in scots pine forests at stand and tree level in relation to some site, stand, and tree characteristics. Population characteristics (age, number and biomass) and distribution of pine mistletoe in the canopy of scots pine trees were also evaluated. A total of 1408 trees were measured in 114 representative sample plots in the Eastern Black Sea Region of Turkey. Of the measured trees, 648 (46%) were mistletoe infected and 760 (54%) were uninfected. The 6-class dwarf mistletoe rating system (DMRS) was used for infection severity rating. Correlation analysis results indicated significant relationships between mistletoe infection severity and stand and tree characteristics. The t-test results showed that there was a significant difference between mean stand and tree characteristics in mistletoe infected and uninfected stands. The results of the binary logistic regression analysis indicated that altitude and stand volume were the most significant predictor of the distribution of pine mistletoe at stand level. As for the population characteristics of pine mistletoe, the results indicated that the life span of pine mistletoe was about 24 years and that biomass distribution gradually increased from lower to upper part of the crowns.