The physical and chemical properties were analyzed according to land characteristics required to evaluate the suitability of frankincense (Styrax sp.). Several criteria representing land quality include temperature (tc), water availability (wa), oxygen availability (oa), nutrient retention (nr), erosion hazard (eh), and flood hazard (fh). The determination of land characteristics related to nutrient retention (nr), such as texture, Cation Exchange Capacity (CEC), acidity (pH), organic carbon, and base saturation, was adjusted to the rooting depth of the planted crops, and then categorized into land suitability classes based on interval values referring to FAO (1976).

 

Land suitability based on soil biophysical properties or land resources prior to the use of inputs to overcome constraints is referred to as actual land suitability. Evaluation of land suitability outside the natural habitat was also conducted in the first year, aimed at developing gambier and frankincense cultivation. The analysis used the matching method based on predetermined criteria with soil analysis results and field surveys. The evaluation of gambier land suitability in its natural habitat (Pakpak Bharat Regency) and frankincense in its natural habitat (North Tapanuli and Humbang Hasundutan Regencies) was intended to obtain land characteristics based on soil physical, chemical, and biological properties as well as climate. The analysis used the back-proving method to establish the land suitability criteria for gambier/frankincense in their natural habitats.