INSECT PESTS AND ARTHROPOD PREDATORS ASSOCIATED WITH TREE-TURF LANDSCAPES

Sweep-nets and pitfall traps were used to examine the distribution and dynamics of predominant predators and pests in turfgrass foliage in p arks, golf courses and suburban/rural landscapes in 1991 and 1992. Ara neae, Formicidae, and Coccinellidae were the most abundant predators i n the sweeps, while Araneae, Formicidae, and) Carabidae were the most abundant predators in the pitfall traps. In both years, Araneae compri sed over 60% of the total predators in the sweep samples. Formicidae ( >70%) and Araneae (13-19%) were the most abundant arthropod predators in the pitfall samples. Cicadellidae, Chrysomelidae, and Orthoptera ac counted for over 96% of the prey in the sweep samples, while Cicadelli dae, Orthoptera (grasshoppers and crickets), and Aphididae comprised o ver 90% of the prey in the pitfall samples. Abundance of predators and prey, and prey/predator ratios fluctuated with site, date, and distan ce from the trees. During the season, high prey/predator ratios usuall y preceded peak prey abundance in the sweep samples. Predators usually were more prevalent in sweep samples closer to tree borders, while pr ey populations tended to be higher at distances further from the tree borders. These results suggest that tree borders provide food, shelter , and refuge for predators during periods of environmental stress.