In many aquatic systems, cascading trophic interactions are important determinants of community structure, via top-down (predation) and bottom-up (productivity) factors. In contrast, little is known of the importance of these factors in the structuring of diverse terrestrial communities. This two-year study monitored the responses of a semi-arid terrestrial arthropod community to predator (wolf spiders and ants) and nutrient manipulations. Preliminary results from the first year of the experiment indicate variation in abiotic factors, and intraguild and non-consumptive interactions may play important roles in suppressing the effects of top-down and bottom-up forces in this system.