Aroostook Hills Maine biophysical regionThe Aroostook Hills Biophysical Region is part of the Northeastern Mixed Forest Province and the Aroostook Hills and Lowlands Ecoregion Section. There are 3 Forest Provinces, 6 Ecoregion Sections, and 19 Biophysical Regions in Maine.


Province: Northeastern Mixed Forest

The Northeastern Mixed Forest Province is characterized by a modified continental climatic regime with a maritime influence along the Atlantic Ocean. Winters are moderately long with continual ground snow cover.  Annual precipitation is generally equally distributed with a peak during summer.  Vegetation of this area consists of forests that provide a transition between boreal conifers and broadleaf deciduous.


Ecoregion Section: Aroostook Hills and Lowlands

The Aroostook Hills and Lowlands Section is a glacially scoured and dissected peneplain; terrain is gently rolling and pitted outwash plain with scattered low mountains. Bedrock consists of weakly metamorphosed sedimentary formations of shales, sandstones, and limestones.  Vegetation is mainly forests of spruce-fir and maple-beech-birch cover types.


Biophysical Region: Aroostook Hills

The Aroostook Hills Biophysical Region is 92% forested. The spruce-fir forest type represents 47% of those acres.

The top three tree species in this region (based on the stocking of live trees per average forested acre) are:

  1. Balsam Fir (47 trees per acre) means 47 live trees (5.0”+ DBH) per forested acre
  2. Northern White Cedar (30 trees per acre)
  3. Red Spruce (20 trees per acre)

This graph shows major tree species/species groups, live tree stocking (trees/acre), and how much they contribute to the overall stocking for the Aroostook Hills Biophysical Region:

Aroostook Hills Biophysical Region hardwood and softwood tree species* All data are based on the Maine Forest Inventory & Analysis, 2015 (United States Department of Agriculture, Forest Service)

Check out the other bioregion in the Northeastern Mixed Forest Province and the Aroostook Hills and Lowlands Ecoregion Section:


To learn more about Maine’s Biophysical Regions, download this comprehensive document from Maine Natural Areas Program (2014):