Eucalyptus camaldulensis is one the important fast growing exotic species in Nepal but its growth performance assessment was not so far done. Thus, this research was objectively carried out to assess the growth performance and relating their growth to soil nutrients in E. camaldulensis plantation forest. Sagarnath Forestry Development was selected for the study site. Stratified random sampling was carried out to collect the samples. Altogether 60 sample plots (40 for plantation, 10 for singling and 10 for doubling) having 1 to 10 years age. Diameter and height, crown height, crown diameter, fork information of 600 plants were measured as well as spacing was recorded. The age of the plantation was noted from plantation report and age of singling and doubling from the harvesting register. Meanwhile, 120 soil samples were collected from 40 plantation site from 0-10, 10-20 and 20-30cm depths. The basal area, volume, biomass and carbon were analyzed, as well as N, P, K, C, pH and bulk density were analyzed in lab. Moreover, inferential and descriptive analysis were analyzed. The result showed that overall growth performance of Eucalyptus camaldulensis with respect to height, diameter, and volume was significantly different according to site quality. The growth of site quality I of E. camaldulensis of SFDP was shown the best performance. The average diameter, height and volume increments were 2.8cm, 3.36m and 0.027m3 respectively in site quality I. The soil N, P, K and pH varied according to depth of sites. For the greater production of timber, it was needed maximum pH (5.83 - 8.37). The maximum NPK values were 0.175%, 300.89kg/ha and 194kg/ha respectively in site quality I. The plant volume was increased till the age of 9 year and then its increment was fallen so, for the maximum growing stock in short rotation in E. camaldulensis it need to harvest at the age of 9 year. It needs to maintain the spacing to obtain the straight and healthy bole. It was found that increasing the spacing has positive effect in diameter and height increment. This study will be useful to see the effect of spacing and soil fertility on growth performance.
Keywords: Eucalyptus camaldulensis, SFDP, growth, plantation, singling, doubling, spacing.