Table 9.2a. Relative standard errors (%) of area of forest land by IUCN1 category, age class and boreal zone in Canada.
Boreal zone IUCN category Age (years) Total
1-20 21-40 41-60 61-80 81-100 101-120 121-140 141-160 161-180 181-200 201+ Other2
Non-boreal NA 3.52 2.94 2.73 2.85 3.08 4.37 4.33 5.21 6.04 7.34 3.87 4.87 1.10
IA 50.65 57.71 51.26 48.03 52.29 54.72 66.00 87.02 75.76 - 77.08 99.65 22.55
IB 54.64 40.34 30.75 20.78 21.98 28.25 24.87 36.72 39.30 36.06 21.21 85.97 9.63
II 38.80 15.96 13.03 11.48 11.54 14.80 14.48 17.27 17.83 17.68 10.28 47.15 4.44
III 82.41 59.78 55.23 66.84 89.97 69.76 66.09 - 100.00 - 69.88 98.45 30.71
IV 32.65 31.72 24.31 30.44 23.60 62.65 37.16 68.23 90.20 - 70.08 46.63 13.07
VI 79.41 99.42 99.92 99.95 99.95 99.95 - - - - - 99.95 67.51
OTHER 85.22 66.15 70.04 70.55 53.17 99.99 - - - - - 93.08 33.52
Subtotal 3.50 2.89 2.65 2.72 2.94 4.16 4.13 5.07 5.88 6.67 3.60 4.85 1.07
Boreal NA 3.15 2.35 2.04 1.81 1.75 1.78 1.96 3.29 7.02 11.75 7.98 3.23 0.72
IA 72.82 73.42 53.75 49.29 44.92 73.47 69.63 100.00 - - - 0.00 25.81
IB 21.54 15.09 12.14 11.07 12.58 13.05 12.21 30.43 36.83 72.88 27.59 22.71 4.76
II 20.68 10.88 8.55 7.61 7.57 8.33 8.29 15.10 20.54 32.45 19.20 16.46 3.19
III - 66.20 53.68 73.64 67.83 75.32 76.89 - - - - - 30.07
IV 47.67 24.55 30.91 26.70 19.20 36.45 21.04 51.24 75.49 100.00 66.87 69.69 11.27
V 100.00 - 100.00 100.00 - 100.00 100.00 - - - - - 54.21
VI 90.42 78.99 61.41 61.17 42.48 39.03 100.00 100.00 - - - 100.00 25.62
OTHER 52.55 29.60 23.79 25.10 25.87 18.00 21.60 68.39 - 100.00 - 100.00 9.45
Subtotal 3.07 2.26 1.95 1.73 1.68 1.72 1.87 3.20 6.60 11.26 7.12 3.16 0.69
Canada NA 2.43 1.89 1.67 1.54 1.53 1.66 1.82 2.85 4.80 6.23 3.48 2.71 0.61
IA 41.63 58.04 37.89 34.61 35.89 52.01 57.53 94.99 75.76 - 77.08 99.65 18.40
IB 21.24 14.33 11.30 9.89 11.07 12.18 11.46 24.02 30.58 34.61 16.82 22.06 4.27
II 18.46 8.99 7.17 6.40 6.33 7.34 7.23 11.39 13.96 16.17 9.06 16.06 2.59
III 82.41 53.74 38.56 50.07 55.58 63.03 51.27 - 100.00 - 69.88 98.45 21.60
IV 30.21 19.49 22.05 20.94 14.96 32.63 19.41 46.32 58.79 100.00 53.66 66.62 8.69
V 100.00 - 100.00 100.00 - 100.00 100.00 - - - - - 54.21
VI 88.75 76.41 55.61 52.87 41.84 39.01 100.00 100.00 - - - 88.55 24.55
OTHER 46.80 28.04 22.64 24.16 24.87 17.92 21.60 68.39 - 100.00 - 92.66 9.15
Total 2.39 1.83 1.60 1.48 1.46 1.61 1.73 2.75 4.50 5.74 3.21 2.66 0.58
Source: Canada's National Forest Inventory, combined remeasured (2007-2017) and projected (2006-2017 with NFI projection system) data (Version 3.1, October 2025) (http://nfi.nfis.org)
Note: The Non-boreal zone in the Arctic ecozones (Arctic Cordillera, Northern Arctic, Southern Arctic) are not inventoried. The total land and water area amounts to approximately 252,202.08 thousand ha.
1 IUCN: International Union for Conservation of Nature (http://www.iucn.org). Data obtained from the Canadian Protected and Conserved Areas Database (CPCAD) (https://www.canada.ca/en/environment-climate-change/services/national-wildlife-areas/protected-conserved-areas-database.html).
2 Missing or unknown age class.
International Union for Conservation of Nature (IUCN) category
IUCN Category Description
NA Not protected
Ia Protected area managed mainly for science
Ib Protected area managed mainly for wilderness protection
II Protected area managed mainly for ecosystem protection and recreation
III Protected area managed mainly for conservation of specific natural features
IV Protected area managed mainly for conservation through management intervention
V Protected area managed mainly for landscape/seascape protection and recreation
VI Protected area managed mainly for the sustainable use of natural resources
Other Protected with missing or unknown category