Invasive forest pests have seriously harmed our environment and imposed significant costs on our economy. The U.S. Department of Agriculture (USDA) is the lead agency for responding to forest pests and coordinates with the Department of Homeland Security (DHS) to prevent pests from entering the country. GAO issued two reports in 2006 on these programs. This testimony describes (1) the status of USDA's efforts to eradicate the Asian longhorned beetle, emerald ash borer, and Phytophthora ramorum; (2) the factors affecting the success of those eradication efforts; and (3) areas of continued vulnerability in regard to preventing the arrival and spread of forest pests. On the basis of the available evidence, it appears that the Asian longhorned beetle will be eradicated in the three states that have infestations, although funding reductions have extended the likely completion date. In contrast, the emerald ash borer and P. ramorum--the pathogen that causes Sudden Oak Death--are likely to continue to infest and damage forest ecosystems in the Midwest and on the West Coast, despite efforts to control them. The success of the federal responses to these infestations has been affected by several factors. First, the unique biological characteristics of each species greatly influences the ability to effectively control them. Second, quarantines have helped contain the spread of the pests, but implementing and enforcing quarantines has been difficult. Third, the only available method for eradicating these pests is to destroy infested trees and plants--a costly and sometimes impractical approach. Fourth, despite budgeting over $420 million to control these three pests, USDA program managers told GAO that funding has not been sufficient to fully implement their programs. We also found that USDA had not adequately prepared up-to-date management plans to provide decision makers and the public with current information on the extent of the infestation, eradication goals, and long-term funding needs. We identified areas of vulnerability that we believe increase the risk of future forest pest infestations. Specifically, we found that despite efforts to expand USDA's forest health monitoring programs, they do not adequately provide for comprehensive monitoring in urban forests or other locations considered at high risk from pest invasions. Monitoring in such areas is important because they are common destination points for internationally traded cargo, which is a frequent pathway for pests. Improvements could help prevent situations such as those experienced with the Asian longhorned beetle, the emerald ash borer, and P. ramorum, in which years of delay in detection allowed them to become established before control programs began. In our report on port inspections, we found that DHS has not used a risk-based staffing model to assign newly hired agricultural specialists to ports of entry. As a result, DHS does not have assurance that staff are assigned to areas of greatest vulnerability. In addition, despite an interagency agreement intended to facilitate coordination between DHS and USDA, agricultural specialists are not consistently receiving notifications of changes to policies and urgent inspection alerts in a timely manner. We also reported that DHS has allowed the canine inspection program--dogs trained to locate items that might harbor pests--to deteriorate. Dozens of canine units are vacant, and the proficiency scores of the remaining canine units have declined.