Porang (Amorphophallus Muelleri Blume) contain quite high glucomannan (15-64% dry basis). Porang  are used as raw materials for food and industry since 1,000 years ago in Japan and China. The high content of glucomannan in porang makes this plant much sought after, especially in the food and health industries. Porang plants need to be researched so that they can be intercropped for oil palm and rubber. Analysis of drainage, texture, coarse material, soil depth, peat thickness and peat maturity was carried out using the borring method and field soil physics tests were carried out. Observation of the level of slope and erosion hazard using a clinometer. And for observations of puddles, surface rocks and rock outcrops with a percentage (%) visualization of the rock volume in the field. Meanwhile, the value of CEC, base saturation, and organic C was obtained from soil analysis resulting from borring sampling in the laboratory. Based on observations and analysis, gardens A, B and C were obtained according to the suitability of the S3 land. To increase the added value, porang is produced in the form of chips. The factory construction investment requires working capital funds and an investment of IDR 3,176,308,600. Investment analysis with tuber seeds showed a positive NPV of Rp. 14,021,379,827.63, IRR >20% and a payback period of 2 years, while the construction of a factory with frog seed cultivation showed a positive NPV of Rp. 3,976,301,962.35, IRR >20%. and Payback Period 4 years 2 months. Based on the two alternatives above, it can be concluded that the investment in building a factory in A plantation by cultivating tuber seeds is better than frog seeds which are shown to have better NPV and Payback Period values

Abstrak Porang digunakan sebagai bahan baku makanan dan industri sejak 1.000 tahun yang lalu di Jepang dan China. Kandungan glukomanan yang tinggi pada porang membuat tanaman ini banyak diminati terutama dalam industri makanan dan kesehatan. Tanaman porang perlu diteliti agar dapat ditumpangsarikan untuk kelapa sawit dan karet. Analisis drainase, tekstur, material kasar, kedalaman tanah, ketebalan gambut dan kematangan gambut dilakukan dengan metode bor. Pengamatan tingkat kemiringan lereng dan bahaya erosi menggunakan klinometer. Pengamatan genangan air, batuan permukaan dan singkapan batuan dengan visualisasi persentase (%) volume batuan di lapangan. Sedangkan nilai KTK, kejenuhan basa, dan C organik diperoleh dari analisis tanah hasil borring sampling di laboratorium. Berdasarkan pengamatan dan analisis diperoleh kebun A, B dan C sesuai dengan kesesuaian lahan S3. Untuk meningkatkan nilai tambah, porang diproduksi dalam bentuk keripik. Investasi pembangunan pabrik tersebut membutuhkan dana modal kerja dan investasi sebesar Rp 3.176.308.600. Analisis investasi dengan bibit umbi menunjukkan NPV positif sebesar Rp. 14.021.379.827.63, IRR >20% dan payback period 2 tahun. Kata kunci : Porang, Kelapa Sawit, Karet, Chip porang, Tumpang sari     Abstract   Porang  are used as raw materials for food and industry since 1,000 years ago in Japan and China. The high content of glucomannan in porang makes this plant much sought after, especially in the food and health industries. Porang plants need to be researched so that they can be intercropped for oil palm and rubber. Analysis of drainage, texture, coarse material, soil depth, peat thickness and peat maturity was carried out using the borring method.. Observation of the level of slope and erosion hazard using a clinometer. The observations of puddles, surface rocks and rock outcrops with a percentage (%) visualization of the rock volume in the field. Meanwhile, the value of CEC, base saturation, and organic C was obtained from soil analysis resulting from borring sampling in the laboratory. Based on observations and analysis, gardens A, B and C were obtained according to the suitability of the S3 land. To increase the added value, porang is produced in the form of chips. The factory construction investment requires working capital funds and an investment of IDR 3,176,308,600. Investment analysis with tuber seeds showed a positive NPV of Rp. 14,021,379,827.63, IRR >20% and a payback period of 2 years.   Keywords: Porang, Palm Oil, Rubber, Chips, Intercropping