The result of example discussed the relations between the nests of red imported fire ant and farming ground, and public facilities. We also predicted the possibility of the directions of the nest dispersals. During the long term eradication on Solenopsis invicta at the Chiayi county government nursery, we conducted the pit fall traps to monitor the S. invicta density. The results showed that 1 trap captured 60 S. invicta per day before eradication, and then dropped to zero S. invicta after 5 months. Although we captured 0.08 S. invicta (2 S. invicta among 24 pitfall traps) on April 20, 2005, but no S. invicta were captured by August 25, 2005.