Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Phase portrait for simultaneous changes to concern level (f) and local cost of firewood (Cl). The dark region represents containment of the infestation while the light region represents continued spread.
