The U.S. Forest Service is intensifying its efforts to protect national forests from invasive species and diseases that kill trees, promote wildfires and threaten water supplies.

Agriculture Deputy Undersecretary for Natural Resources Arthur “Butch” Blazer said Tuesday that invasive species cost the national economy more than $100 billion annually, and the problem is getting worse as warming temperatures allow invasive species to spread.

Among the steps the policy sets out are creating a national database for infestations and control efforts, requiring loggers and other contractors to take steps to control invasive species, and working with neighboring landowners.

Invasive Species coordinator Mike Ielmini says the policy will be a foundation to build a stronger program, which to date has been fragmented.