Effects of spacing and post-planting treatments on survival and growth of Fraxinus angustifolia seedlings.

This study was conducted at a bottomland hardwood site with heavy textured soil in Akyazi, Turkey to determine the effect of initial spacing (3.0 x 3.0, 3.0 x 2.0, 2.5 x 1.6 and 2.5 x 1.2 m) and post-planting treatments (untreated check, moving, hoeing, disking, and hoeing plus disking) on early survival and growth of Fraxinus angustifolia Vahl. One-year old bare-root seedlings (70±5 cm in height) were hand-planted in December 2004. Through three years survival was perfect with a rate of 98% in all treatments. Spacing and the interaction between spacing and post-planting treatment did not significantly affect seedling growth through three years. However, height and diameter growth increased over time and differed significantly among post-planting treatments. The hoeing and hoeing plus disking treatments gave the highest growth, and resulted in about 31% increase in diameter and height increment, and in total diameter and height about 20%. These results suggest that post-planting treatments on bottomland sites with heavy textured soil give promising results.

Effect of N and NPK fertilizers on early field performance of narrow-leaved ash, Fraxinus angustifolia.

The effect of fertilization in the first growing season on early survival and growth of narrow-leaved ash (NLA) (Fraxinus angustifolia ssp. oxycarpa) was evaluated throughout the first 3 years of growth in Adapazari, Turkey. A randomized complete block design with four replications was established to investigate fertilization effects. Granular N urea [46%, (NH2 )2CO, NH2-N] and NPK (15/15/15%; NH3-N, P2O5, K2O) fertilizers were applied in mid-May of the first growing season. Fertilization treatments per tree were control, 67 g NPK (equal to 10/10/10 g N/P2O5 /K2O tree–1), 133 g NPK (20/20/20 g N/P2O5 /K2O tree–1), 33 g urea N (15 g N tree–1) and 54 g urea N (25 g N tree–1). After three growing seasons under these fertilizer treatments, 98% of trees were still viable. Compared to the control treatment, fertilization had a large and positive effect on diameter and height growth during the first 3 years of growth. However, since there were no significant differences among the fertilized plots in terms of tree diameter and height growth, addition of P and K to the fertilizer regime was not beneficial. The results show that N fertilization in the first growing season has the potential to improve early field growth of narrow-leaved ash.

Seed germination of three Ulmus species from Turkey as influenced by temperature and light.

The effect of temperature and light on the germination performance of Ulmus minor, Ulmus glabra and Ulmus laevis were studied in this research. Seeds were germinated under constant temperatures of 20 and 25 degrees C and alternating temperatures of 25/15 and 30/20 degrees C. Within each temperature regime, seeds were subjected daily to the following photoperiods: total darkness and 8 hr photoperiod. Temperature and light affected seed germination percentage (GP) and germination rate expressed as peak value (PV) in Ulmus minor and 25 and 30/20 degrees C under light gave the highest GP (>95%) and PV (>23). The temperatures of 25/15 and 30/20 degrees C gave the highest GP (>89%) in Ulmus glabra and light did not significantly affect GP. But the highest PV in Ulmus glabra was found at these temperatures under light. Germination percentage of Ulmus laevis was not affected by temperature and light, but the alternating temperature of 30/20 degrees C produced the highest germination rate under darkness.