Physical and chemical properties of oil palm land which overgrown with weeds at different plant age

Abstract

Large plantations such as oil palm plantations are usually covered by several weed species which occasionally function as a land cover. Soil samples were obtained through Simple Random Sampling on various types of ground cover weeds, e.g Asystasia intrusa, Eleusine indica, Cyperus kyllingia Endl. and Cyrtococcum oxyphyllum Stapf., in 7-year old oil palm stands, and Asystasia intrusa, Cyperus kyllingia Endl., Cyrtococcum oxyphyllum Stapf. and Cyperus rotundus, in 6-year old stands. Each sample was randomly obtained from each replicate plot at a depth of 0-20 cm (layer 1) and 20-50 cm (layer 2) at 5 points. Variables of soil chemical properties observed were N-total, P-available, K-total, C-organic and soil pH, while the physical properties observed were water content (%) and volume weight, using the gravimetric method. The results showed that the presence of weeds beneath the oil palm stands in plantation areas did not continuously have a negative effect on the growing environment. In this study, the presence of 4 (four) weed species under 6 and 7 years old were found around old oil palm stands and classified as dominant existences actually have a positive tendency to influence the quality of physical and chemical properties of soil under oil palm stands.