BIOMASS OF SOME GRASS SPECIES UNDER DIFFERENT AGES AND SPACINGS OF MELIA AZEDARACH LINN. PLANTATION.

Abstract

The study on biomass of four grass species, namely Panicum maixmum, Brachiaria ruziziensis, Panicum maximum c.y. hamil and Panicum maximum var. trichoglumes, under 4x4 m aud 2x8 m spacings of Melia azedarach Limn. plantation at Ongpra Reforestation Unit, Suphan Buri Province, were carried out during January to December 1986. The experimental method used in the study was a completely randomized factorial design. Statistical analysis of biomass showed that there was significant difference (P<0.01) existed among grass species, also significant difference (P<0.01) between spacings, from Panicum maximum (1007.1 kg.ha^-1) followed by Brachiaria ruziziensis (915.4 kg.ha^-1) Panicum maximum c.v. hamil (809.7 ka.ha^-1) and Panicum maximum var. trichoglumes (408.1 kg.ha^-1), Apparently, the biomass varied with the amount of rainfall. The average dry matter of grass species in 2x8 m spacing was higher than that 4x4 m spacing of Melia azedarach Linn. plantation. They were 1053.8 kg.ha^-1 of biomass under 2x8 m spacing and 516.3 kg.ha^-1 under 4x4 m spacing. It was recommended that the appropriate spacing for the agroforestry practice under the forest plantation should be 2x8 m rather than 4x4 m.