According to the enemy release hypothesis, species introduced to a new range have fewer natural enemies in the introduced range than in the native range. This hypothesis has been used to explain the success of alien plant invasions. If true, the proliferation of alien plants in the landscape will impact ecosystem function. This study examines herbivore and predator populations found on native and alien plants in an experimental field in Delaware. Twelve plant species, primarily herbaceous annual plants commonly found in waste areas, were selected. Six alien species and six native species were planted into two treatments. Insects were sampled by sweep netting and destructive sampling of whole plants. Destructive samples were taken by placing a bag over the plant, cutting the plant off at the ground, returning the bags to the lab and collecting insects found in each bag. Insect biomass of whole plant samples were standardized to account for the effect of plant size. Sweep net samples showed a greater number and biomass of insects in the native treatment as compared to samples obtained from alien treatment. These results also suggest an increased insect biomass on the native plants when compared to the alien plants.