About two-thirds of the state has slid to a warmer half zone since that last edition in 2012, according to the USDA. As the climate has changed, so have farming plans in Maine.

The USDA divides the United States into seven planting regions, known as hardiness zones, which were most recently updated in 2023.The maps below show these planting regions.

The USDA 2012 Plant Hardiness Zone Map. USDA The USDA Plant Hardiness Zone Map divides the United States and Canada into 13 zones, based on the average annual minimum winter temperature.

Planting zones are warming — affecting which plants thrive in different U.S. regions. This trend is likely to continue as global temperatures rise. ... Zone shift. Presque Isle, Maine ...

PORTLAND, Maine (AP) — Maine forestry officials are planning a wide expansion of quarantine zones to try to prevent the spread of three invasive forest pests that pose threats to the state’s ...

The expanded quarantine zones are important “to protect Maine’s forest, timber, and wildlife resources from this destructive pest,” the department said in documents about the adelgid.