Uncaria gambir (Ug) is the main ingredient for producing Gambir which is an international trading commodity that Indonesia has shared its production of 80% in the world. This paper investigates the type of Ug cultivation system in West Sumatra and its contribution to farmers’ income security. Rapid rural appraisal was used for collecting data. Economic analysis is carried out consisting of Benefit and Cost ratio (B/C Ratio), net present value (NPV), internal rate of return (IRR), sensitivity test on the discount rate and Gambir production. Six Ug cultivation systems were found, namely Ug-Mono, Ug-Rubber, and Ug-Areca nut in Lima Puluh Kota regency (LPKR) and in Pesisir Selatan regency (PSR) Ug-Durian, Ug-Durian-Jengkol and Ug-Durian-Petai. In general, The Ug cultivation systems combined with Durian and Jengkol or Petai, that were found valuable additional crops, were more stable in income generation against to the fluctuation of Ug production and Gambir price. Among the six, the highest B/C Ratio was found in Ug-Durian-Jengkol (2.8) while the lowest was in Ug-Mono and Ug-Rubber (1.9). Moreover, Ug-Durian-Jengkol show better NPV and IRR in the most conditions of Gambir price from 10,000 to100,000 Rp kg^－1 as well as Gambir production from 2,400 to 4,800kg y^－1. On the other hand, NPV and IRR of Ug-Mono, -Rubber or -Areca nut systems sharply decreased with the decrease of Gambir price. These systems relied more on Ug production and Gambir price in the income generation. It exhibited the vulnerability of income structure of these systems. From the results, to secure farmers’ income from volatility of Ug production and Gambir price, this research suggested Ug cultivation systems combining with durian or other profitable cash crops in West Sumatra.

Community forests in Indonesia are important suppliers of wood resources for the wood industry. In the present study, stress-wave velocity of stems, log characteristics (taper, green density, and dynamic Young’s modulus), and wood properties (basic density, compressive strength parallel to grain, modulus of elasticity [MOE], and modulus of rupture [MOR]) were investigated for three fast-growing tree species grown in community forests in Indonesia: Acacia mangium Willd., Maesopsis eminii Engl., and Melia azedarach L. Based on the bending properties, the MOE values of laminae (30×150mm in cross-section) and glulam (six layers, 90×150mm in cross-section) were simulated. The mean values of simulated MOE in the laminae were 8.93, 6.82, and 8.63GPa for A. mangium, M. eminii, and M. azedarach, respectively. When the laminae from a species were randomly laminated, the simulated MOE values of glulam were 8.94, 6.82, and 8.66GPa for A. mangium, M. eminii, and M. azedarach, respectively. When laminae with a high, medium, and low MOE were laminated at outer, middle, and inner layers of glulam, respectively, the simulated MOE values of glulam increased by about 5% to 15% compared to the values of a randomly laminated one. It is concluded that glulam with a high MOE can be produced from fast-growing tree species grown in community forests in Indonesia.