The effect of nitrogen fertilization and root undercutting on growth and survival of beech (Fagus sylvatica L.) in cultivation

Abstract

Background. The paper presents an analysis of the effect of nitrogen fertilization and root undercutting on growth and survival rates of 2-year old seedlings of European beech (Fagus sylvatica L.) after a vegetation season of their growth in cultivation. Material and methods. The experimental material came from an experimental site established in the Jawor Forest District administered by the Regional Directorate of the State Forests in Wrocław. Analyses were conducted on young European beech trees after a year of growth in a second-growth forest, established using 2-year old seedlings produced by various methods. Two factors were investigated in the experiment, i.e. nursery production method (seedlings with no root undercutting vs. seedlings with root undercutting) and the effect of varying nitrogen fertilizer application rate (25 kg×ha-1 and 50 kg×ha-1). Results. The experiment showed a strong effect of seedling production technology and nitrogen fertilization on survival rates, height and increment in height of beech seedlings. It was found that in cultivation the seedlings with no root undercutting, fertilized with nitrogen fertilizer applied at 25 kg×ha-1, were the tallest. However, those seedlings had the lowest survival rates. It was shown that the varied nitrogen fertilizer application rates had a lesser effect on biometric traits of European beech in comparison to the effect of root undercutting. An interaction was also observed for the investigated factors in terms of their effect on survival rates and morphological characteristics of young beech seedlings. Conclusion. The reduction of root systems at the stage of nursery production produced by root undercutting in European beech seedlings may be compensated for by a higher nitrogen fertilizer application rate. The reduction of nitrogen fertilizer dose to 25 kg×ha-1 does not disturb growth in height in cultivation of beech seedlings with no root undercutting. Nitrogen fertilizer application rate may be lowered to 25 kg×ha-1 when root undercutting is eliminated in nursery production; however, a potential drawback of this method is connected with the risk of low reforestation success.