Trees of Ontario, region by region

Hudson Bay Lowlands and the Boreal forest

The Hudson Bay Lowlands hold, in the province's words, one of the largest expanses of wetland in the world, and only about a quarter of the region has forest cover. Trees are mostly stunted tamarack and black spruce along riverbanks and on better-drained ground. Tamarack is the conifer that turns gold and drops its needles in autumn; the tamarack profile explains its soft needle tufts.

The Boreal forest is Ontario's largest region, about 50 million hectares and two-thirds of the province's forest. Learn these first, with clues from Natural Resources Canada's factsheets and the Ontario ministry:

• Black spruce (Picea mariana): short, dull greyish-green needles 8 to 15 mm on hairy twigs, and small rounded cones clustered near the top of the tree. Ontario describes it on wet or organic sites, often in large, nearly pure stands.
• Jack pine (Pinus banksiana): short, sharp, slightly curved needles in pairs, two to four centimetres long, and curved cones that open after a forest fire (Ontario ministry). It favours sandy or rocky sites in the north.
• Balsam fir (Abies balsamea): flat, fragrant needles and sticky resin blisters on the trunk; often grows in clumps under other trees.
• Poplar (Populus): Ontario's ministry groups trembling aspen, largetooth aspen and balsam poplar. Trembling aspen has nearly round leaves on a flattened stalk that make the crown flutter. See the poplar guide.
• White birch (Betula papyrifera): smooth white bark that peels like paper.
• Eastern white cedar (Thuja occidentalis): flat, fan-shaped sprays of scale leaves; Ontario notes it prefers swampy areas but also grows on rocky uplands.

Great Lakes–St. Lawrence forest

This is Ontario's second-largest forest region, about 20 million hectares stretching along the St. Lawrence to Lake Huron and west of Lake Superior along the Minnesota border. It is dominated by hardwoods, and much of it is uneven-aged, with young and old trees in the same stand.

• Eastern white pine (Pinus strobus), Ontario's official tree: soft needles in bundles of five, six to twelve centimetres long by the ministry's figures, and long, hanging cones. Canadian Heritage's Ontario page gives May 1, 1984 as the adoption date and calls it the province's tallest tree, able to live more than 250 years.
• Red pine (Pinus resinosa): long, sharp, dark green needles in pairs, 10 to 16 cm. To separate it from white pine and jack pine, see red pine vs white pine.
• Sugar maple (Acer saccharum): five-lobed leaves with rounded notches; the leaf on the Canadian flag, as the ministry puts it. Red maple (A. rubrum) has V-shaped notches and toothed edges; red maple vs sugar maple compares them.
• Yellow birch (Betula alleghaniensis): silvery grey to yellowish bark in thin curling shreds, on cool, moist upland sites.
• Eastern hemlock (Tsuga canadensis): short flat needles in two rows with white lines beneath, on cool moist soils near water, often with yellow birch and maple.
• Red oak (Quercus rubra): leaves with bristle-tipped lobes. Ontario's ministry says red oak is the most common of its native oaks, ahead of white and black oak.

The Deciduous (Carolinian) forest in the far south

The Deciduous forest region, also called the Carolinian zone, covers almost 3 million hectares, about 3% of Ontario. The province calls it the region with the greatest tree diversity and the lowest proportion of forest: farms and cities cover most of it, and forest covers about 10%. The Tree Atlas species pages give these ranges and clues:

• Tulip tree (Liriodendron tulipifera): leaves 7 to 12 cm, flat across the top with four pointed lobes; yellow-green and orange tulip-shaped flowers in spring; 25 to 35 m tall. Native only on the south shore of Lake Huron, the north shore of Lake Erie and the Niagara Peninsula.
• Sassafras (Sassafras albidum): leaves with no lobes, two lobes or three lobes on the same tree, smooth-edged and blunt-tipped. Uncommon, it grows in the Carolinian zone north to about Toronto, often in colonies.
• Kentucky coffeetree (Gymnocladus dioicus): doubly compound leaves whose central stalk is often mistaken for a twig, and hard, leathery pods 12 to 20 cm long that hang on through winter. It grows naturally only in Southwestern Ontario and is a species at risk in the province, though it is widely planted.
• Black walnut (Juglans nigra): compound leaves of 14 to 22 leaflets, the end leaflets smaller than the rest, and dark, thickly ridged bark. Common in moist, low ground in Southwestern Ontario and often planted farther north. The walnut guide separates it from butternut.
• Sycamore (Platanus occidentalis): large, maple-like leaves and patchwork bark flaking to show white, green and cream. Scattered in Southwestern Ontario to the Toronto area, with outlying pockets as far north as Collingwood–Thornbury. The sycamore page covers it and the planted London plane.

The province also lists butternut, black gum, hickories, many oaks, redbud and cucumber tree, Ontario's native magnolia, in this region.

The most common trees in Ontario

The Ontario Ministry of Natural Resources' Common trees page in Forest resources of Ontario 2021 (updated 26 June 2025) states that black spruce is Ontario's most common tree, poplar the second, jack pine the third and sugar maple the fifth. The page does not name the measure behind that ranking. Its "total area as lead species" figures for the managed forest zone match it, so we rank by that measure below. Shares are our arithmetic against the 36.6 million ha total in the same page's 2021 lead-species table.

Ranked by the area that contains each species instead, white birch (17.1 million ha) and poplar (16.6 million ha) come ahead of jack pine, so the order depends on the measure. For the national picture, see the most common trees in Canada.

Field guides and a photo app for Ontario trees

The Ontario government's Tree Atlas, published in 2021 and updated 5 May 2026 when we read it, lists 79 native species or species groups. Pick a point on its map or one of five regions (Northwest, Northeast, South Central, Southwest, Southeast) and the list narrows to the native trees of that area, each with a page on identification and growing conditions. Natural Resources Canada's factsheets add measurements and range maps, and the Canada hub lists every provincial tree.

When the leaves are out of reach, Tree Identifier names a tree from one photo of a leaf, needle bundle, bark or fruit, with a follow-up chat for questions such as "is this a red or a white pine?". It shows no confidence score and no look-alike list, so confirm with the clues above. Its Tree Map keeps each located find, useful for coming back to a Carolinian tree when it flowers.