Teak plantations in Java show severely declining productivity due to various disturbances. The risk of stand destruction, however, is still ignored in determining annual allowable cuts, partly due to the lack of reliable methods to estimate the rate of stand destruction. This study therefore proposed an alternative method, based on the theory of survival analysis coupled with forest register data, for estimating survival probability and destruction rate of teak plantations. We used the forest register data of teak plantations in Kebonharjo, Central Java, for the period 1977-2007. Survival and destruction of plantations were modeled using probability distribution models. To estimate model parameters, we used the maximum likelihood estimation method designed for left-truncated and right-censored data. Results showed that survival probability and destruction rate varied over stand age and planning period. Rates of stand destruction were relatively low (<2% per year) in the period 1977-1987, but increased up to 3% and 14% per year in the period 1987-1997 and 1997-2007, respectively. The highest rate of destruction mostly occurred in young stands (&le;30 years old), indicating an alarming condition for the sustainability of teak plantations. The survival and destruction models are useful for forest managers to quantify the range of historical variability in forest disturbances and to support the development of alternative harvest scheduling methods that incorporate the risk of stand destruction for teak plantations in Java. The proposed method can also be applied to other regions, especially when only forest register data are available.

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A study has been conducted on management operations followed by rural farmers in their homestead agroforestry systems. Despite high socio-economic contribution, the management of this farming system is traditional in nature; scientific knowledge and techniques are lacking. Analysis of field data showed that an average of 16.9 seedlings were planted per farm in the preceding year and of those 15.6 were fruit species and 1.4 were timber species. The overall seedling survival rate was 77%. The farmers depended mostly on internal inputs although supplementary external inputs are also fed used. The farmers reported that they manually carried out cultural operations like weeding, mulching and fencing. Of the tree level management, pruning, pollarding, and thinning were done. For maintaining homestead forest production and its efficient management the study recommended judicious incorporation of drought tolerant native species at the farm level, creating appropriate institutional mechanisms within the forest department and development of market systems for homestead grown products.

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