TITLE: TREE CLASSIFICATION BASED ON TREE RING QUALITY IN CENTRAL JAVA

Abstract

In Central Java Indonesia, many tropical trees don't produce distinct rings. This has caused difficulties in defining tree rings for dendrochronology.  The quality of tree rings is very important to know the past environmental conditions including climate, weather, rainfall, disease, and fire. The purpose of this study was to classify wood based on the quality of tree rings. The method used in this study was a survey in Banyumas, Cilacap, Purbalingga, Banjarnegara and Wonosobo, Central Java. The material used were samples of wood pieces from felling in the area. Furthermore, the assessment of the ring quality was carried out by polling and sending questionnaires to respondents to assess each tree species. Each ring consisting of early wood and late wood was observed under a microscope. The results of this study indicate that there are three groups of trees, namely trees with: 1) Very distinct annual rings including Pinus merkusii, Melia azedarach, Toona sureni, and Hevea brasiliensis, 2) Medium annual rings including Swietenia mahagoni, Hibiscus tiliaceus, and Persea americana, 3) unclear or absent tree rings including Gnetum gnemon, Parkia speciosa, and Baccaurea racemosa. An important finding that can be concluded is that the majority of distinct annual rings come from medium to high lands.