KEYWORDS (SNI 14-1031(SNI 14- -1989, and inorganic matters (Ca, Mg, K, Na, Fe, Mn, and Cu) Ca, K, Mg, Na, and Fe were 408-2919 ppm; 69 -23705 ppm; 947-1653 ppm; 4 -31 ppm; and 0 -326

Information concerning ash materials and acidity (pH values) within the wood of teak (Tectona grandis L.f.) plantations is especially limited. Samples taken from the stands of Perhutani plantation (Madiun and Randublatung) and community forests in Kulon Progo (Temon and Kalibawang) were analyzed to determine the ash content, metallic elements constituting the ash fraction, as well as pH values. The ranges of ash content were 0.55-3.88% whereas acid insolube ash content (silica/silicates) were 0.12-2.45%. The main four inorganic elements in wood were assayed by atomic absorption. The levels of these metals ranged from 340-4774 ppm for calcium, 17-4399 ppm for potassium, 143-1676 ppm for magnesium, and 0247 ppm for iron. Further, the pH values varied from 5.33-7.25. Differences of inorganic variables and pH values in wood were found between trees of different growth-site and radial position. The variation among the different sites was significant in the contents of silica, calcium, magnesium, potassium, and sodium while the effects of radial direction were significant in the silica and potassium levels. Ash content was positively correlated with acid insoluble ash (r = 0.77) and potassium content (r = 0.47). Furthermore, pH values were positively correlated with the magnesium content (r = 0.65) and negatively correlated with potassium (r = -0.49) and sodium contents (r = -0.55). A description of the chemical properties of the soil, however, was not sufficient in determining whether there was a relationship between the levels of metal elements or pH values in the wood and in the soil.

Indonesia government pays little attention to address impending threat of the existences of upland smallholder farmers due to insufficient farm income. This condition poses an imminent threat to national food security. One of the initiatives to address the condition is participatory action research project conducted by Faculty of Forestry UGM with 12 upland smallholder farmers in Wonogiri regency from 2016 to 2018. The result of the participatory action research project showed that although the 12 smallholder farmers practice cropland agroforestry system in marginal land, their increased rice production could improve farm income, be similar in rice field and support national food security. Therefore, this study aimed at investigating lesson-learned of the participatory action research project. This study was conducted on January-March 2020, used participant observation and semi-structure interview methods to collect data from the 12 smallholder farmers. After the collected data were analyzed by descriptive method, this study founded four points of lesson-learned including (1) finding a responsive smallholder farmer group; (2) minimizing negative role of local elite; (3) maximizing positive role of local elite; (4) implementing modified technology package.