Study of some Chemical Properties of Ultisols Soils Based on the Existence of Earth Worms

— The purpose of the study was to determine some of the chemical properties of the soil on Ultisols inhabited and uninhabited by earthworm populations. The research was carried out from April to June 2019, taking soil samples on mixed garden land in the Bukit Pinang Urban Village, Samarinda and soil analysis at the Soil Science Laboratory, Faculty of Agriculture, Mulawarman University, Samarinda, East Kalimantan Province. The research activities are: field observations, determining the location of soil sampling, soil sampling, collection and calculation of earthworms, and analysis of soil chemical properties in the laboratory. The data collected were: population density of earthworms, and some soil chemical properties: soil pH C-organic, N-total, P-available, and K-available. The results showed that Ultisols inhabited by worm populations had several soil chemical properties (soil pH, C-organic, N-total, P-available and K-available) which were higher than Ultisols soils that were not inhabited by earthworms .