Summary Mistletoe infection results in substantial growth losses in mistletoe‐infected forests. This study reports and evaluates the results of retrospective analyses of radial growth of Scots pine (Pinus sylvestris) in relation to the level of infection of pine mistletoe (Viscum album ssp. austriacum). A total of 43 Scots pine trees were destructively sampled from different sites. Of these trees, 14 were uninfected and 29 were infected. Infection classes were determined using six‐class dwarf mistletoe rating system (DMRS). All needle and mistletoe biomass were removed completely and weighed for each sampled tree. Subsamples from needles and all mistletoe biomass were taken to the laboratory for oven‐dried weight determinations. Five‐cm‐thick wood discs were cut from the stem at the breast height (1.3 m) to determine annual basal area increment for the last 25 years. In addition to DMRS, new infection classes were created using mistletoe‐to‐needle biomass (MB/NB) ratio. The results showed that the radial growth losses could be as much as 41% to 64% at different infection levels. The rate of growth loss in relation to DMRS and MB/NB ratio was similar, but with a larger variability in DMRS values. The results showed that both DMRS rating and MB/NB ratio seem to be important for quantifying growth loss on Scots pine trees infected with mistletoe. The results of this study can also be invaluable in modelling the effects of mistletoe on the growth of Scots pine trees.

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Monochamus galloprovincialis (Olivier) is the vector of the pinewood nematode, Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle, in Europe and Asia. Reproduction is probably the most important event in the life history of insects and may be affected by a number of factors, such as seasonal changes in larval or adult nutrition. In this study the effect of season on the reproductive potential of M. galloprovincialis females reared in black pine logs was investigated by constructing fertility tables for each of 43 pine logs that differed only in the season that they were cut. Population parameters were compared among 3 seasonal cohorts. The intrinsic rate of increase and related population parameters of the beetles that emerged from autumn logs were mostly higher than for beetles that emerged from spring and summer logs. These results suggest that seasonal differences in the nutritional quality of the logs (for immature development) and pine twigs (for adult feeding) may have caused the observed differences in M. galloprovincialis survival and reproduction.

Calabrian pine (Pinus brutia Ten.) is the most widely distributed coniferous species in Turkey. Forests mostly composed of Calabrian pine constitute the most flammable forests in fire sensitive regions of the country. Especially, regenerated and immature stands of this species have the most fire-prone fuel type. This study evaluates the results of vertical crown fuel distribution and develops some crown fuel models to explain canopy fuel characteristics in natural Calabrian pine stands. A total of 35 trees were cut down and crown fuels were determined vertically. The highest crown fuel load was generally situated in the middle part of tree crown. The percentage of needles in each crown section increased gradually from the beginning of lower parts to the upper parts of tree crowns for three stand types. Total crown fuel loads were determined as 5.66 kg for regenerated stands, 11.57 kg for immature stands and 17.44 kg for middle age stands, respectively. Correlation and regression analyses were performed to determine the relationship between needles, branches, available fuels, total crown fuels and tree properties. The results of crown fuel distribution and the allometric equations developed in this study can be used to predict vertical fuel load at any height from ground to the top of Calabrian pine stands. The results of this study will contribute to the verification and evaluation of fuel load prediction models in use, and enhance the understanding of crown fire behavior mechanism in forest fires.

Aim of study: Pinus brutia is the most widespread conifer forest tree species in Turkey. It is mainly distributed in fire sensitive regions of the country. The economic importance in wood production and the deterministic role in forest fires fighting activities make this forest tree more valuable and important. This study describes crown fuel load of suppressed trees in non-treated young Calabrian pine stands. Area of study: The study area is located in the Western Black Sea region of Turkey. Sampling plots were located in Hacımahmut Forest Planning Unit. Material and methods: Trees were selected from non-treated young Calabrian pine plantation stands and used to obtain live crown fuel load and characteristics. For this purpose, 30 young suppressed trees were cut and sampled. Main results: In sampled trees, oven dried total live needle biomass ranged between 0.54 kg and 3.19 kg and total live crown fuel load chanced between 1.96 kg and 12.73 kg. Regression models to estimate crown fuel load were developed according to some tree characteristics. Models developed explained 0.79 to 0.89% of the observed variation. Highlights: Regression analysis indicated that the total live crown fuel load was strongly correlated with both diameters at breast height (DBH) and crown base height (CBH).