Non-native forest pathogens kill many thousands of trees annually in the United States. Two serious fungal diseases are oak wilt in the East and sudden oak death (SOD) in the West. Information on economic costs and losses to landowners and municipalities is limited, especially for residential areas. Forest Service researchers predicted the spread of SOD in California and oak wilt in Anoka County, MN, over the decade 2010-2020 and then predicted annual expenditures for oak treatment, removal, and replanting and property value losses associated with tree mortality. For SOD in California, they predicted that annual expenditures could reach almost $1 million and annual property value losses, up to $13 million. For oak wilt in a single county in Minnesota, they predicted annual expenditures of $2 to 6 million. Although the predicted amounts are substantial, they are, nevertheless, lower bounds on total economic losses because of reduced ecosystem services such as water quality and increased safety hazards. Quantifying expenditures and losses to landowners is critical to strategies for prevention, management, and research of diseases and pests in forests.