Michigan is a quarantine state for Gypsy Moths. This means that logs, pulpwood, wood chips, nursery stock, Christmas trees, mobile homes, recreational vehicles, lawn furniture, and other outside household articles, cannot be moved to a non-quarantine state without first being inspected. If you are moving from one state to another, the moving company must have a signed certificate saying the items being moved have been inspected and are free of all Gypsy Moth life forms. Inspection can be through a USDA-trained certified pesticide applicator, or can be Self-Inspection. A guide and checklist is available from the US Department of Agriculture's Animal & Plant Health Inspection Service.

It is also important to remember that Gypsy Moths can be moved from one place to another on firewood. Usually it is the egg masses that are moved, but it can also be other life stages. Even if you're only moving firewood a short distance, it's important to realize that you may be moving the gypsy moth too. Other pests and diseases that are spread through the movement of firewood are Oak Wilt, Beech Bark Disease, and the Emerald Ash Borer.

more info: http://ceris.purdue.edu/napis/news06/fr40875-gypsyMoth.txt