Yield and Nutrient Contents of Various 5-Year-Old Eucalypt Clones in the Upper Northeast

Abstract

The yield and nutrient content of various 5-year-old eucalypt clones in the upper northeast of Thailand were investigated at three sites—namely, Wang Sam Mo, Udon Thani province (WM), Ban Phaeng, Nakhon Phanom province (BP) and Seka, Bueng Kan province (SK). A randomized complete block design (RCBD) with 3 blocks was applied. There were 5 clones (total 16 trees per clone) in each block with 3x3 m spacing. For this study 5 eucalypt clones were used consisting of SF1, SF2, SF3, SF4 and SF5.

The results showed that the aboveground biomass of SF5 eucalypt clone was the highest at WM as 144.59 t.ha^-1, while at BP, SF1 clone was the highest (129.73 t.ha^-1) and at SK, SF4 clone was the highest (158.26 t.ha^-1). The aboveground biomass of various eucalypt clones were statistically significant differences.

The highest nutrient content accumulation in the 5 eucalypt clones was calcium and the next high accumulation in order were nitrogen, phosphorus, potassium and magnesium, respectively. The same trend was evident at all 3 sites. The highest nutrient concentration was in the leaf followed by the branch and stem, respectively. The accumulation of nutrient was the highest in the stem because the stem had the highest biomass production and it was varied according to the clone and/or site.