We estimated the age of plantation-grown trees lacking distinct and consistent annual rings to examine whether an anatomical method for determining the vessel traits of wood is effective in the tropical rain forest climate. Stem disks from 1 Dipterocarpaceae and 2 Meliaceae species for which the planting year was known were collected, and radial strips were sawn out from 2 different radii on each disk. We measured mean vessel lumen area (MVLA) and vessel frequency (VF) and found that radial changes in the 2 variables showed cyclic variation in all samples. The cycle number of both MVLA and VF mostly matched the tree age when they were analyzed with proper radial resolution. The number and shape of the cyclic variations were different between the 2 radii; this inconsistency could partly be ascribed to asynchronous cambium activity. The result implies that (1) the selection of sample species is important and (2) more than 1 radius should be analyzed to increase the accuracy of estimation. Thus, we concluded that vessel traits are important growth-ring indicators in the humid tropics, but a single application of this method of ring analysis may not be sufficiently accurate in age estimation. Further research on the factors affecting vessel formation will make the method more effective.

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Vegetable production by most farmers in the Philippines is highly dependent on pesticides. Pesticides are commonly applied before pest species are identified and intensity assessed. Current pesticide practice can lead to as many as 19 applications in 45 days per crop of pakchoi. The integration of integrated pest management (IPM) into crop management strategies is prompted by our view that pesticide use is excessive and costly, can lead to reduced pesticide efficacy and to human health problems from consumption of vegetables with pesticide residue. We have therefore, embarked upon a program among vegetable growers to demonstrate that pest identification, monitoring of pest intensity, and judicious use of effective pesticides can be combined into a holistic strategy of crop management. For this purpose a series of IPM training materials was developed. The majority of farmers attending farmer field schools assessed the IPM materials as very useful. Prior to being trained in IPM, farmers used 300 % the amount of insecticide but only 68% of the fungicide amount than researchers who followed IPM guidelines. Use of fungicides increased because training made them aware of the damage caused by pathogens which had previously been ignored. Pesticide residue was detected in 7 of 9 field samples. In two, the amount detected exceeded maximum residue levels (MRL) established by ASEAN for Chlorpyrifos and in one sample the amount exceeded the MRL for Cypermethrin. The results are critically discussed in regard to the implementation of IPM materials.

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The process of implementing the Community Forest (Hutan Kemasyarakatan: HKm) scheme in Gunungkidul district of Java, Indonesia, was explored by a case study method. Topics focused on were: 1) the local agrarian context in which the scheme was introduced, 2) the household characteristics of participants and non-participants, and determinants for participation, and 3) the conditions of the tree planting, and the effects the planted trees had on rural livelihoods. Transferred state forestland in the studied sub-village had been extensively encroached upon and utilized for crop cultivation by local people at the time HKm was initiated. The primary determinant of whether a household participated in HKm was whether the household had previously occupied any faming plots in the current HKm area. While intercropping between the rows of planted trees was allowed, reforestation on the encroached plots led to a loss of farming opportunities among the participant households as the canopy of planted trees closed over. It was revealed that providing official long-tem usufruct through the scheme worked adversely for local livelihoods in the case of Gunungkidul; reforestation was carried out at the expense of de facto land use opportunities for local people. The results suggested that implementation of community-based forest management schemes or programs without careful consideration for existing local agrarian contexts, especially forestland encroachment, may generate unexpected outcomes.

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