Juniper is one of the three main tree species in Central Anatolia, where it grows under extreme environmental conditions. Although dendrochronological studies of juniper are challenging because of cross-dating problems, these types of studies on long-lived tree species have the potential to provide long time series, which reflect changes in climatic conditions. Juniper has been neglected as a scientific research subject in Turkey due to degraded populations and low economic expectations. This study analysed the distribution and present state of Juniperus spp. (Juniperus excelsa M. Bieb., Juniperus oxycedrus L., and Juniperus foetidissima Willd.) stands and used dendrochronological data to examine relationships between growth and environmental parameters. We hypothesised that there may be differences in the radial growth of juniper in areas of different exposure in drought regions. During a field survey, we sampled 31 plots of 25 m × 20 m and data, including information on wood cores, were collected. For dendrochronological investigation, 95 wood cores were manually measured and cross-dated. Residual chronologies of tree-ring width series of juniper from four wind directions and regional chronology of Kirikkale and Ankara Province were provided and similarities between the chronologies were tested using Gleichläufigkeits test. The relationships between climate parameters and growth were examined using a simple correlation analysis and multiple linear regression model analysis in SAS 9.0 program and response function analysis in the DENROCLIM2002 program. The results of this study indicated that Juniperus spp. in Central Anatolia are sensitive to environmental parameters and mainly respond to changes in precipitation. Juniper show differences in radial growth in areas of different exposure in drought regions. We conclude that juniper may offer an excellent opportunity for large-scale dendrochronological and dendroecological studies in drought regions.

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Aim of study: The intention of current study is to compile information on female fertility variation and estimate some parameters related to fertility in the seed orchard for 2015. Area of study: The seed orchard was established in April 2004 in Eflani of Karabuk, Turkey. Material and Methods: The seed orchard included 823 ramets of 26 clones at 5m x 5m. Five ramets per clone were chosen randomly and female strobili in 130 ramets were counted in June 2015. All of the female strobili over the entire crown were counted on all chosen ramets. Female fertility variation, status number and relative status number were estimated. Main results: Average numbers of female strobili per clone were ranged from 4.2 to 75.0. The most fertile clone was #351, the less fertile one was #354. The top 30% of clones produced 50.6% of total female strobili. Most of female strobili were appeared single but the rest of them were formed clusters. Number of strobilus of clusters was ranged from 2 to15. In analyses of variance, differences in clonal female strobilus production were not statistically significant (P=0.07). Female fertility variation

In economic and biological terms (rapid growth, the ability to produce seeds at an early age, etc.) Pinus brutia Ten. is one the most important forest tree species in Turkey. Considerable progress has been made in Pinus brutia Ten. breeding program and both phenotypical and according to the results of progeny trials, totaling 615-hectare seed orchardshas been established. Pinus brutia Ten. seed orchardshas reached 43% of the total orchard area and covered the largest area. To acquire information on the management of seed orchards, top pruning has been carried out on three Pinus brutia Ten. seed orchards of different ages (old, middle-aged and young). Two top pruning regimes were applied in these three seed orchards, once in 2008 to the old orchard, while a single topping regime was applied in 2008 and 2012 to the middle-aged and young orchards.Each year, the height, diameter at breast height, and bi-directional crown diameter were measured, and all conelets and cones on ramets were counted beforeand after pruning. At the end of four years, control ramets in old and young seed orchards had higher values of height, diameter at breast height, and volume indexcompared to the middle-aged orchard. On the other hand, even though the control ramets in the middle-aged seed orchard reached a greater height, pruned ramets reached a greater volume index and diameter at breast height. While the height differences observed between control and pruned ramets in all seed orchards at the beginning eventually decreased, it was observed that the heights of pruned ramets grew proportionally larger. No difference was founded between the control and pruned ramets in terms of cone and conelet production. Pruning intervals and regimes varied in old, middle-aged and young seed orchards, and it was acknowledgedthat top pruning could be used for old, middle-aged and young seed orchard managements.

Genetic parameters of 9 oriental sweetgum (Liquidambar orientalis Mill.) populations were estimated at a common garden test. Open-pollinated seeds were collected from 16-27 families for each population. The common garden test was established in 2009 using a randomized complete block design in 25 blocks with single tree plot, with each block included 223 families. Breast height diameter, height and crown diameter were measured at the age of five. The purpose of study was to compare the genetic parameters of optimal and marginal populations and to assess the findings for genetic conservation. The study revealed significant variability in all traits evaluated. In variance components, variation among populations was three times higher than that of families. Individual heritability estimates for breast height diameter, height and crown diameter pooled across the whole dataset (marginal and optimal populations) were 0.21 ± 0.04, 0.27 ± 0.04 and 0.11 ± 0.03 and additive genetic coefficients of variation were 13.4%, 9.1% and 7.1%, respectively. Individual heritability estimates for breast height diameter, height and crown diameter in marginal and optimal populations were 0.27 ± 0.10, 0.19 ± 0.08 and 019 ± 0.08 and 0.19 ± 0.04, 0.29 ± 0.05 and 0.09 ± 0.03, respectively. Additive genetic coefficients of variation for breast height diameter, height and crown diameter were 16.7%, 8.3% and 10.8% in marginal and 12.8%, 9.1% and 6.2% in optimal populations, respectively. While breast height diameter and crown diameter were more heritable for marginal populations, height was more heritable for optimal populations. These findings are discussed in terms of genetic conservation of oriental sweet gum.

One of the main issues facing the forestry sector is balancing the demand for forest products and the sustainable management of forest ecosystems. Efficient plantation management and intensive silviculture practices are needed to grow timber in forest tree plantations. Due to the tangible impact on wood production, the plantations area in the world has constantly increased during the last several decades. The annual increase of plantation was 3.3 million ha in the period of 1990-2015. Over the past decades, tree improvement programs have progressed to the second, third, and fourth cycles to provide genetically improved planting stock to plantations. Substantial genetic gain has been realized from major tree improvement programs around the world. The effect of tree breeding on wood and fiber production per unit area has further increased by the modern plantation silvicultural applications, such as soil preparation, fertilization and thinning. Combination of tree breeding and silvicultural applications shortened the rotation ages of plantations, increasing the wood and fiber output per unit time. In this study, the importance of silvicultural treatments and plantation management has been reviewed and how such practices could enhance sustainable management of natural forests.

Key message In this study, genetic variation in polycyclic growth was investigated in a young Pinus brutia Ten. study in Turkey. The number of flushes was partially under additive genetic control and was moderately correlated with the tree height at age 4.• Context Pinus brutia is the most economically important tree species in Turkey. Previous limited studies suggested that its cyclic shoot elongation pattern can be useful for selecting seed sources for breeding and conservation of genetic resources.• Aims Understand the degree of genetic control of terminal shoot growth, number of flushes, and total tree height at early ages and assess the genetic relationships between the traits to guide decisions for breeding and gene conservation.• Methods Open-pollinated progenies of 188 trees from eight different seed sources were tested in three locations in the Aegean region of Turkey. Variance components, heritability and additive genetic correlations were estimated for tree height, terminal shoot length, and number of flushes.• Results Traits were moderately under genetic control at the family. Terminal shoot length explained 76% of the variation in tree height. A strong genetic correlation (0.96) was found between tree height and terminal shoot length, while the number of flushes had a moderate genetic correlation with height (0.59). Northern seed sources tended to display less height growth, partially due to fewer flushes and lower shoot length.• Conclusion Shoot elongation in the species is partially under additive genetic control and could be useful to select for early height in breeding programs.

West Blacksea fir (Abies nordmanniana (Stev.) Spach subsp. equi-trojani) is an endemic species of Turkey. Six populations, four of which are a seed stand and three gene conservation forests (Akyazi-Dokurcun, Aladag-Sarialan, Kizilcahamam-Guvem, Safranbolu-Safranbolu), a Nature Reserve Area (Istanbul-Beykoz) and a natural forest (Pinarbasi-Kurtgirmez) were selected to study. Cones were harvested from 118 trees in six populations. Some seed characters obtained from cones were measured and evaluated. The average seed width, length, and thickness were 6.63 mm, 12.06 mm, and 3.46 mm, respectively. The average 1000 seed weight was 82.80 g. Statistical analyses indicated significant differences at the population level in all characteristics except seed length. Regarding genetic similarity, populations were divided into two main groups: East and West. The isolated Istanbul-Beykoz population was similar to the West group showing artificial migration or cut-off from the West group. Due to including seed stand and gene conservation forest, the findings are expected to contribute to forest management, besides Christmas trees and landscape use.