There are many ways to subdivide Ontario geographically. The province can be partitioned on administrative or ecological boundaries, watershed or electoral districts, ownerships or even forest or wildlife management units.

This version of the Forest Resources of Ontario summarizes several commonly referenced subdivisions, focusing on landcover class area rather than detailed FRI summaries. The AOU will be referenced where applicable to highlight area of managed forest within many of these zones.

Rowe's forest regions

J. Stan Rowe was a geo-ecologist that worked for Forestry Canada and the University of Saskatchewan. In 1959 he wrote "Forest Regions of Canada" which is perhaps one of the most commonly used systems to describe Canadian forests. The map layers used in this version of "The Forest Resources of Ontario" varies slightly to those used previously, due to better mapping standards, and is based on the 1972 version of Rowe's map.

Each forest region is characterized by its climate, forest ecosystems and wildlife species. North-south gradients in temperature and east-west gradients in precipitation largely determine the extent of these forest regions. Most of Ontario’s population lives within the Great Lakes and Deciduous forest regions. Since Rowe’s did not define forest regions into the great lakes, some area has been omitted from the summaries, primarily great lakes water. The AOU is almost exclusively on the boreal and great lakes forest regions.

Total area by land class and forest region (hectares)

Land class Hudson Bay Lowlands Boreal Forest Great Lakes–St. Lawrence Forest Deciduous Forest Total
Water 1,876,738 6,381,062 2,411,969 29,552 10,699,321
Wetland 7,595,680 1,602,817 240,368 36,285 9,475,151
Field/Agriculture 0 64,739 3,301,828 2,028,417 5,394,985
Other 368,672 594,430 767,045 388,113 2,118,259
Treed Wetland 9,760,624 4,008,146 1,004,660 197,638 14,971,067
Forest 6,309,004 37,053,429 12,410,324 307,231 56,079,988
Total Area 25,910,718 49,704,622 20,136,193 2,987,236 98,738,770

Total area by forest region within the AOU (hectares)

Area Hudson Bay Lowlands Boreal Forest Great Lakes–St. Lawrence Forest Deciduous Forest Total
Total Area 25,910,718 49,704,622 20,136,193 2,987,236 98,738,770
Total Area within AOU 599,184 30,199,930 14,179,894 0 44,979,007
Crown Forest within AOU 342,152 20,320,726 6,309,357 0 26,972,234

Map of Rowe's forest regions

map of Rowe's forest regions including Hudson Bay Lowlands, Boreal Forest, Great Lakes - St. Lawrence Forest, and Deciduous Forest.

Enlarge map of Rowe's forest regions

Area by region

pie chart of the area by region including army green for Hudson Bay lowlands, dark green for boreal forest, grey for great lakes - st. lawrence forest, and dark brown deciduous forest.

Hudson Bay lowlands forest region

The Hudson Bay Lowlands is the northernmost forest region in Ontario, and is dominated by bogs and fens, sparse slow growing forest and tundra. Productive forest is generally made up of stunted Tamarack and Black Spruce growing along river banks and other well-drained areas. White Birch, dwarf birch and willow are the common deciduous trees in this forest region.

Total area by land class and ownership–Hudson Bay lowlands (hectares)

Land class Crown Parks and protected areas Other Total
Water 1,619,983 252,661 4,094 1,876,738
Wetland 6,618,956 958,638 18,086 7,595,680
Field/Agriculture 0 0 0 0
Other 120,207 246,619 1,846 368,672
Treed Wetland 8,886,344 829,125 45,154 9,760,624
Forest 5,917,102 346,337 45,565 6,309,004
Total Area 23,162,592 2,633,381 114,745 25,910,718

Boreal forest region

Ontario’s boreal forest is the largest forest region in Ontario and Canada and contains two-thirds of Ontario’s forest. It extends from the northern limits of the Great Lakes–St. Lawrence forest to the Hudson Bay Lowlands.

Coniferous (softwood) and mixed-wood forests dominate the Boreal region. The main conifer species are black and White Spruce, Jack Pine, Balsam Fir, Tamarack and eastern White Cedar. The predominant deciduous (Hardwood) species are Poplar and White Birch.

Total area by land class and ownership–boreal forest (hectares)

Land class Crown Parks and protected areas Other Total
Water 5,101,278 1,144,127 135,657 6,381,062
Wetland 1,467,074 120,944 14,800 1,602,817
Field/Agriculture 3,792 42 60,905 64,739
Other 401,627 115,543 77,260 594,430
Treed Wetland 3,605,735 324,858 77,553 4,008,146
Forest 31,435,390 3,988,659 1,629,380 37,053,429
Total Area 42,014,895 5,694,173 1,995,555 49,704,622

Great lakes–St. Lawrence forest region

The Great Lakes–St. Lawrence forest is the second largest forest region in Ontario. This forest extends along the St. Lawrence River across central Ontario to Lake Huron and west of Lake Superior along the border with Minnesota.

The Great Lakes–St. Lawrence forest is dominated by Hardwood forests, featuring species such as maple, oak, Yellow Birch, white and Red Pine. Coniferous trees such as White Pine, Red Pine, Hemlock and White Cedar, commonly mix with deciduous broad-leaved species, such as Yellow Birch, sugar and Red Maples, basswood and Red Oak.

Total area by land class and ownership–great lakes forest (hectares)

Land class Crown Parks and protected areas Other Total
Water 1,642,259 420,732 348,977 2,411,969
Wetland 49,593 19,332 171,444 240,368
Field/Agriculture 22,799 5,991 3,273,038 3,301,828
Other 158,851 80,937 527,257 767,045
Treed Wetland 191,470 46,350 766,840 1,004,660
Forest 6,764,873 1,503,264 4,142,187 12,410,324
Total Area 8,829,845 2,076,606 9,229,743 20,136,193

Deciduous forest region

The deciduous forest is the southernmost region in Ontario, dominated by agriculture and urban areas. This region has largely been cleared with scattered woodlots remaining on sites too poor for agriculture. This forest generally has the greatest diversity of tree species, while at the same time having the lowest proportion of forest.

It has most of the tree and shrubs species found in the Great Lakes–St. Lawrence forest, and also contains black walnut, butternut, tulip, magnolia, black gum, many types of oaks, hickories, sassafras and red bud &mdAsh; species commonly found in Ohio, Pennsylvania and the Carolinas in the USA.

Total area by land class and ownership–deciduous forest (hectares)

Land class Crown Parks and protected areas Other Total
Water 1,056 379 28,117 29,552
Wetland 869 1,625 33,791 36,285
Field/Agriculture 1,304 2,138 2,024,975 2,028,417
Other 280 680 387,153 388,113
Treed Wetland 892 2,538 194,209 197,638
Forest 1,330 4,671 301,231 307,231
Total Area 5,730 12,031 2,969,475 2,987,236