This study was done during 1984 in a commercial crops at the Bogota Plateau. Low numbers of arthropods were found in the samplings. o. arma tus was the most abundant arthropod, located around the root area of carnation and chrysantemum plants, and usually between O and 20 cm in the soil. This species was shown to be a pest on carnation and chrysantemum roots, decreasing height and weight of chrysantemum plants and decreasing the number of cuttings produced by carnation plants. The amount of damage is determined by the number of individuals present in the population.