Plants & trees
Identify a tree by its leaf
A botanical key asks four questions in a fixed order, and they matter far more than the leaf outline everyone starts with. Are the leaves opposite or alternate on the twig? Is each leaf one blade or several leaflets? Is the edge smooth, toothed or lobed? Answer those three and most trees are already down to a handful. Shape comes last.
Narrow it down
Showing all 43 trees
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White oak
Quercus alba
Five to nine deep lobes with rounded tips and no bristles, pale grey-green above and whitish beneath. Rounded lobes place it in the white oak group; bristle tips would make it a red oak.
In the record 47,555 georeferenced records · half of them Apr–Aug · most distinctive in December · mostly from the United States check on GBIF
Identifying oaks by leaf -
Northern red oak
Quercus rubra
Seven to eleven shallow lobes, each ending in several sharp bristle tips, with sinuses that cut less than halfway to the midrib. Dull green above, paler below.
In the record 226,793 georeferenced records · half of them May–Aug · most distinctive in November · mostly from the United States check on GBIF
Oak leaf identification -
Pin oak
Quercus palustris
Five to seven bristle-tipped lobes with very deep U-shaped sinuses cutting almost to the midrib, giving a skeletal outline. Lower branches droop, which nothing else in the genus does.
In the record 147,819 georeferenced records · half of them Aug–Oct · most distinctive in December · mostly from the United States check on GBIF
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Live oak
Quercus virginiana
An oak that does not look like one: small, leathery, unlobed evergreen leaves with rolled-under edges and a fuzzy grey underside. Acorns are the only obvious clue it is a Quercus.
In the record 9,706 georeferenced records · half of them Jan–Jun · most distinctive in December · mostly from the United States check on GBIF
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Sugar maple
Acer saccharum
Five palmate lobes with smooth-sided sinuses that are U-shaped at the base and no small teeth along the lobe edges. The Canadian flag leaf. Opposite arrangement confirms the genus.
In the record 59,528 georeferenced records · half of them May–Aug · most distinctive in October · mostly from the United States check on GBIF
Maple leaf identification -
Red maple
Handle with careAcer rubrum
Three to five shallow lobes with V-shaped notches between them and irregular teeth along the edges, silvery beneath, on red leaf stalks and red twigs.
In the record 133,130 georeferenced records · half of them Mar–Jul · most distinctive in October · mostly from the United States check on GBIF
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Silver maple
Acer saccharinum
Five deeply cut lobes with narrow sinuses reaching most of the way to the base and a brilliantly silver-white underside that flips up in the wind before rain.
In the record 95,335 georeferenced records · half of them May–Aug · most distinctive in October · mostly from the United States check on GBIF
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Norway maple
Acer platanoides
Broad five-lobed leaf, wider than it is long, with each lobe drawn out into a fine bristle point — and a bead of milky sap at the cut end of the leaf stalk. That sap is the identification.
In the record 1,034,483 georeferenced records · half of them Apr–Jul · most distinctive in June · mostly from Germany check on GBIF
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Boxelder
Acer negundo
The only maple with compound leaves — three to five coarsely toothed leaflets, opposite on the twig, on green or purple-bloomed twigs. Winged maple seeds confirm it.
In the record 254,110 georeferenced records · half of them Mar–Jun · most distinctive in April · mostly from the United States check on GBIF
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White ash
Fraxinus americana
Opposite compound leaves with five to nine stalked leaflets, whitish beneath, on stout twigs with a leaf scar shaped like a smiling crescent under each bud.
In the record 17,819 georeferenced records · half of them May–Aug · most distinctive in September · mostly from the United States check on GBIF
How to identify an ash tree -
Shagbark hickory
Carya ovata
Five leaflets — the top three much larger than the bottom two — with tufts of hair on the teeth, alternate on the twig. The bark peels in long loose strips, which is the faster identification from a distance.
In the record 17,910 georeferenced records · half of them Mar–Jul · most distinctive in February · mostly from the United States check on GBIF
Identifying hickory trees -
Black walnut
Juglans nigra
A very long compound leaf with 15 to 23 narrow toothed leaflets and a terminal leaflet that is often missing or stunted. Crushed leaves smell sharply of walnut husk and stain fingers.
In the record 39,932 georeferenced records · half of them May–Aug · most distinctive in October · mostly from the United States check on GBIF
How to identify a walnut tree -
Paper birch
Betula papyrifera
Small oval-to-triangular leaves with doubly toothed edges — large teeth with smaller teeth on them — on slender twigs, over chalk-white bark that peels in horizontal papery sheets.
In the record 28,894 georeferenced records · half of them Mar–Jul · most distinctive in February · mostly from Canada check on GBIF
Birch tree identification -
American beech
Fagus grandifolia
Neat oval leaves with straight parallel veins running to a small sharp tooth at the end of each one, glossy above. Dead leaves hang on all winter, pale and papery.
In the record 90,676 georeferenced records · half of them Mar–Jul · most distinctive in February · mostly from the United States check on GBIF
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American elm
Ulmus americana
Doubly toothed oval leaf with a strikingly lopsided base — one side of the blade starts noticeably lower on the stalk than the other. Rough as sandpaper on top.
In the record 45,426 georeferenced records · half of them Mar–Jul · most distinctive in March · mostly from the United States check on GBIF
Elm tree identification -
Hackberry
Celtis occidentalis
Lopsided base like an elm, but with three prominent veins fanning out from it and teeth only on the upper two-thirds of the blade. The bark is covered in corky warts.
In the record 28,574 georeferenced records · half of them May–Aug · most distinctive in October · mostly from the United States check on GBIF
Hackberry identification -
American sycamore
Platanus occidentalis
Very large three- to five-lobed leaf, broader than long, with a hollow leaf stalk base that caps the bud. Camouflage-patterned bark flaking to white makes the tree unmistakable in winter.
In the record 50,035 georeferenced records · half of them Feb–Jul · most distinctive in February · mostly from the United States check on GBIF
Sycamore identification -
Tulip tree
Liriodendron tulipifera
Four lobes and a flat, notched top as if the tip had been cut off with scissors. No other North American tree has that outline, and it is decisive on its own.
In the record 77,205 georeferenced records · half of them Apr–Jun · most distinctive in April · mostly from the United States check on GBIF
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Sweetgum
Liquidambar styraciflua
A five-pointed star with finely toothed edges, smelling resinous when crushed. Alternate arrangement separates it from maples, which are opposite and never star-shaped.
In the record 97,409 georeferenced records · half of them Mar–Jul · most distinctive in December · mostly from the United States check on GBIF
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American basswood
Tilia americana
Large heart-shaped leaf with a strongly lopsided base and coarse sharp teeth. Flowers hang from a strap-like pale bract, which is unique among northern trees.
In the record 59,524 georeferenced records · half of them May–Aug · most distinctive in October · mostly from the United States check on GBIF
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Eastern cottonwood
Populus deltoides
A broad triangle with coarse curved teeth on a flattened leaf stalk, so the leaves flutter and rattle in the slightest breeze.
In the record 36,424 georeferenced records · half of them Apr–Jul · most distinctive in April · mostly from the United States check on GBIF
Cottonwood identification -
Quaking aspen
Populus tremuloides
Small round leaves with fine teeth on a flattened stalk, trembling constantly, over smooth greenish-white bark. Grows in clonal stands where every tree turns colour on the same day.
In the record 61,907 georeferenced records · half of them Jun–Aug · most distinctive in June · mostly from the United States check on GBIF
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Black willow
Salix nigra
Long, narrow, finely toothed leaves that taper to a fine point at both ends, often slightly curved, on flexible twigs that snap cleanly at the base.
In the record 16,544 georeferenced records · half of them Mar–Jun · most distinctive in April · mostly from the United States check on GBIF
Willow tree identification -
Black cherry
Prunus serotina
Glossy narrow leaf with incurved blunt teeth, a pair of small red glands where the blade meets the stalk, and a line of rusty hairs along the midrib underneath. Crushed twigs smell of almonds.
In the record 288,858 georeferenced records · half of them Apr–Jul · most distinctive in May · mostly from the Netherlands check on GBIF
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Flowering dogwood
Cornus florida
Opposite oval leaves with smooth edges and veins that curve forward to follow the leaf outline instead of running to the edge. Tear one gently and fine white latex threads stretch across the break.
In the record 42,748 georeferenced records · half of them Apr–May · most distinctive in April · mostly from the United States check on GBIF
Dogwood identification -
Southern magnolia
Magnolia grandiflora
Thick, leathery, glossy evergreen leaves with a rusty felt underside and completely smooth edges. Huge cream flowers in early summer.
In the record 19,648 georeferenced records · half of them Jan–May · most distinctive in February · mostly from the United States check on GBIF
Magnolia species and names -
Northern catalpa
Catalpa speciosa
Enormous heart-shaped leaves in whorls of three, with smooth edges, followed by long bean-like pods that hang all winter. The pods make it identifiable at a hundred metres.
In the record 9,623 georeferenced records · half of them May–Jul · most distinctive in June · mostly from the United States check on GBIF
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Black locust
Robinia pseudoacacia
Compound leaves of rounded blue-green leaflets with smooth edges, and a pair of short sharp thorns at the base of each leaf stalk. Hanging white pea flowers in May.
In the record 496,561 georeferenced records · half of them Apr–Jul · most distinctive in May · mostly from France check on GBIF
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Honey locust
Gleditsia triacanthos
Feathery twice-compound leaves of many tiny leaflets, and on wild trees vicious branched thorns up to 20 cm long growing straight out of the trunk.
In the record 139,443 georeferenced records · half of them Mar–Jul · most distinctive in February · mostly from the United States check on GBIF
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Red mulberry
Morus rubra
The leaves on one tree come in three shapes — unlobed heart, mitten with one lobe, and a three-lobed glove — all coarsely toothed, all bleeding milky sap when torn.
In the record 9,368 georeferenced records · half of them Apr–Jun · most distinctive in April · mostly from the United States check on GBIF
Mulberry tree identification -
Osage orange
Maclura pomifera
Glossy pointed oval leaves with smooth edges, milky sap, and a stout straight thorn at each node. The grapefruit-sized green brain-like fruit removes all doubt.
In the record 28,756 georeferenced records · half of them Jul–Oct · most distinctive in November · mostly from the United States check on GBIF
Identifying Osage orange -
Sassafras
Sassafras albidum
Three leaf shapes on the same twig — plain oval, a mitten with one thumb, and a three-lobed glove — all with smooth edges, and all smelling strongly of root beer when crushed.
In the record 62,820 georeferenced records · half of them Apr–Jul · most distinctive in May · mostly from the United States check on GBIF
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Eastern redbud
Cercis canadensis
Almost perfectly heart-shaped leaves with completely smooth edges and a papery texture, on zigzag twigs. Magenta pea flowers burst directly from the bare branches in spring.
In the record 64,693 georeferenced records · half of them Mar–May · most distinctive in March · mostly from the United States check on GBIF
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Horse chestnut and buckeye
Handle with careAesculus species
Five to seven large toothed leaflets radiating from a single point like fingers, opposite on the twig. No other common tree has palmately compound leaves.
In the record 429,086 georeferenced records · half of them Apr–Jun · most distinctive in April · mostly from the United Kingdom check on GBIF
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Ginkgo
Ginkgo biloba
A flat fan with veins that fork repeatedly and never form a network, usually notched in the middle. Every leaf on the tree turns butter yellow and drops within a day or two.
In the record 60,681 georeferenced records · half of them Jun–Sep · most distinctive in November · mostly from the United States check on GBIF
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Eastern white pine
Pinus strobus
Soft flexible blue-green needles in bundles of five — one for each letter of "white" — with long slender cones. Count the needles per bundle and the pine group follows.
In the record 115,039 georeferenced records · half of them Mar–Jul · most distinctive in February · mostly from the United States check on GBIF
Pine identification -
Red pine and Scots pine
Pinus resinosa, P. sylvestris
Needles in bundles of two. Red pine needles are long and snap cleanly when bent; Scots pine needles are short, twisted and blue-green, over orange upper bark.
In the record 12,319 georeferenced records · half of them Apr–Aug · most distinctive in February · mostly from the United States check on GBIF
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Norway spruce
Picea abies
Stiff four-sided needles attached singly to little woody pegs, so a stripped twig feels rough and warty. Roll a needle between finger and thumb — a spruce needle rolls, a fir needle will not.
In the record 1,007,278 georeferenced records · half of them Jun–Aug · most distinctive in July · mostly from Sweden check on GBIF
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Balsam fir
Abies balsamea
Flat needles with two white stripes underneath, attached by a suction-cup base that leaves a smooth round scar. Cones stand upright on the branch and disintegrate rather than falling whole.
In the record 39,062 georeferenced records · half of them May–Aug · most distinctive in February · mostly from Canada check on GBIF
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Eastern hemlock
Tsuga canadensis
Short flat needles of unequal length in two flat rows, each on a tiny stalk, with two white bands beneath — and a row of small needles lying upside down along the top of the twig.
In the record 64,784 georeferenced records · half of them Mar–Jul · most distinctive in February · mostly from the United States check on GBIF
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Eastern redcedar and arborvitae
Juniperus virginiana, Thuja occidentalis
No needles at all — tiny overlapping scales pressed flat against flattened green sprays, aromatic when crushed. Redcedar carries blue berry-like cones; arborvitae carries small woody ones.
In the record 71,990 georeferenced records · half of them Jan–Jun · most distinctive in February · mostly from the United States check on GBIF
How to identify a cedar -
Bald cypress
Taxodium distichum
Soft feathery needles in two flat rows that turn rust orange and fall in autumn — a deciduous conifer. Woody "knees" rise out of the water around the trunk.
In the record 43,257 georeferenced records · half of them Apr–Aug · most distinctive in November · mostly from the United States check on GBIF
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Douglas fir
Pseudotsuga menziesii
Soft flat needles radiating all around the twig from small raised bases, with pointed reddish buds like a beech. The cone settles it: three-pointed bracts stick out between the scales like the back legs and tail of a mouse.
In the record 164,367 georeferenced records · half of them Mar–Jul · most distinctive in February · mostly from the United States check on GBIF
Identifying Douglas fir
Nothing in this key matches every filter at once. That usually means one observation is off — a colour read in shade, or a size guessed rather than measured. Clear the filter you are least sure about and look again.
Opposite or alternate, first and always
Leaf arrangement is the first question in every serious tree key, and it does more work than any other single character, because the trees with opposite leaves are a short and memorable list.
In eastern North America the mnemonic is MAD Cap Horse: Maple, Ash, Dogwood, Caprifoliaceae (the viburnums, honeysuckles and elderberries) and Horse chestnut. Add catalpa and paulownia, and that is very nearly the whole opposite-leaved tree flora of the region. Everything else — every oak, hickory, birch, beech, elm, cherry, willow, poplar, sycamore, magnolia and locust — is alternate.
So a tree with paired leaves has already been narrowed from several hundred candidates to about seven groups, before you have looked at the leaf itself. That is why the filter is at the top of this key.
Two cautions. Check arrangement on a strong healthy shoot, not on a stressed twig or a sucker, where it can go irregular. And look for pairs of buds rather than pairs of leaves in winter or on a browsed tree — buds keep the arrangement when the leaves have gone.
Simple or compound: the mistake almost everyone makes
A compound leaf looks like a twig with several small leaves on it, and it gets counted as several leaves constantly. The consequence is severe: a walnut counted as simple leaves also appears to be opposite-leaved, and every subsequent step goes wrong.
The rule that settles it: there is a bud in the angle where a leaf joins the twig, and no bud where a leaflet joins the leaf stalk. Find the bud and you have found where the leaf begins. In autumn there is a second confirmation — the whole compound leaf drops as a unit, stalk and all.
Three compound patterns cover the common trees:
- Pinnate — leaflets in two rows along a central stalk: ash, hickory, walnut, black locust, sumac, boxelder.
- Bipinnate — that structure repeated, giving a feathery leaf of many tiny leaflets: honey locust, mimosa, Kentucky coffeetree.
- Palmate — leaflets radiating from one point like fingers: horse chestnut and the buckeyes, and essentially nothing else among common trees.
Palmately compound is worth memorising precisely because it is so rare. If leaflets fan out from a single point and the leaves are opposite, you are looking at an Aesculus, and you can stop.
The oak question, answered in one look
More people ask about oaks than about any other genus, and the whole of North America's several dozen species split cleanly into two groups on one character.
| White oak group | Red oak group | |
|---|---|---|
| Lobe tips | Rounded, no bristle | Pointed, with a fine bristle at the tip |
| Acorn maturity | One season | Two seasons |
| Acorn taste | Low tannin, edible after light leaching | Bitter, needs long leaching |
| Acorn cup interior | Hairless | Hairy |
| Wood | Pores plugged, watertight — barrels | Pores open, not watertight |
| Typical members | White, bur, swamp white, chestnut, post oak | Northern red, black, pin, scarlet, shingle, willow oak |
Some oaks are not lobed at all — live oak, willow oak and shingle oak have plain unlobed leaves — which is why the acorn is worth picking up. Any tree bearing an acorn is an oak, whatever the leaf looks like.
The three trees with three leaf shapes
Sassafras, mulberry and, less famously, some poplars produce unlobed, one-lobed mitten and two-lobed glove leaves on the same branch. This is the single most common reason a beginner concludes they are looking at three trees.
Separating sassafras from mulberry takes two seconds. Sassafras leaves have smooth edges and smell strongly of root beer when crushed. Mulberry leaves are coarsely toothed and bleed milky sap from a torn stalk. Both are alternate, both grow in the same disturbed ground, and both are commonly misidentified as the other.
The general lesson matters more than the two species: sample several leaves before you decide on a shape. Leaves from a shaded interior branch are larger, thinner and less deeply lobed than leaves from the sunlit crown of the same tree; juvenile shoots and stump sprouts are often wildly atypical. Take a leaf from a normal branch in reasonable light, and take three of them.
Conifers: count the needles
The evergreen groups are separated by how the needles attach, and each has a test you can do with your fingers.
- Pines hold needles in bundles wrapped in a papery sheath at the base. Count them: two, three or five. Eastern white pine has five; most hard pines have two or three.
- Spruces have single, stiff, four-sided needles that roll between finger and thumb, attached to small woody pegs that leave a twig rough after the needles fall.
- Firs have single flat needles that will not roll, attached by a suction-cup base leaving a smooth round scar, usually with two white stripes underneath. Their cones stand upright and fall apart on the tree.
- Hemlocks have short flat needles of unequal length in two flat rows, each on a tiny stalk, plus a row lying upside down along the top of the twig.
- Douglas fir is neither a true fir nor a spruce: soft flat needles all round the twig, sharply pointed reddish buds, and a cone with three-pointed bracts sticking out between the scales.
- Junipers, cedars and arborvitae have no needles at all on mature growth — scales pressed flat against flattened sprays, aromatic when crushed.
- Larch and bald cypress are conifers that drop their needles. A bare conifer in January is one of these, not a dead tree.
The old field mnemonic is worth the ten seconds: spruce is square and it spins; fir is flat and it does not.
Photographing a leaf so it can actually be identified
Most failed identifications are failed photographs. Four shots cover it, and they take a minute.
- The whole leaf flat, front-lit, on a plain background, with a coin or a hand for scale. If it is compound, include the entire leaf down to where it joins the twig.
- The underside. Colour, hairs, and the vein pattern on the back separate several pairs that look identical from above — silver maple and red maple, white oak and swamp white oak.
- The twig, showing at least two nodes so the arrangement is visible, plus buds and leaf scars.
- Bark, fruit and the whole tree. Acorns, samaras, pods, cones and berries frequently settle in one glance what leaves cannot settle at all.
And note the location and the setting. A tree in a wet river bottom in Ohio and a tree in dry chaparral in California share no candidate list. Habitat is a filter this key does not have and a botanist uses constantly.
What is in this key
43 trees: the common natives of eastern and central North America, the conifers of the north and west, and the introduced street trees you are most likely to be standing under in a city on either side of the Atlantic. That covers most of what people photograph and leaves out a great deal — the western hardwoods, the desert and subtropical floras, the willow and hawthorn complexes, and every shrub.
Willows, hawthorns, serviceberries and many oaks hybridise freely, and there are species pairs that a professional botanist will not separate from a leaf alone. Where that is true here, the entry names the group rather than pretending to a species. For anything that matters, photograph the leaf, twig, bark and fruit and post it to iNaturalist, where the identification is free and often arrives within a day.
What the observation record shows
Every entry in this key that carries a scientific name is matched against GBIF, the international register of biodiversity records, and against iNaturalist. That puts a hard number behind 43 of the 43trees here: 5,418,033 georeferenced records across the 42 entries that resolve to a single species, spanning 21 families, the oldest of them collected in 1983. The snapshot was taken on 2026-09-04.
That evidence is not spread evenly, and it is worth knowing before you trust a narrow result. The five best-recorded trees in this key hold 57% of all the records between them: Norway maple alone accounts for 1,034,483, while Red mulberry has 9,368. A common thing is common in the data too, so when a filter narrows to one frequent entry and one rare one, the frequent one is usually the answer — and the record count is the quickest way to see which is which. The same skew applies geographically: 39% of these records come from the United States, so the key describes what is reported there far better than it describes anywhere else.
When these are actually reported
Half of every record for this group falls in April–July. A raw month count measures two things at once — when the organism is about, and when people are outdoors with a camera — and the second effect is large enough to give almost anything a summer peak. The line on the figure divides each month by the baseline for every species in every Orvik key, which answers a different question: relative to when people record anything at all, when are these trees recorded? Values above 1.0 are the months that belong to this group rather than to the season. On that measure 28 of the 42trees here peak outside the warm half of the year — Northern red oak, Douglas fir, Pin oak among them. Those are the ones a seasonal rule of thumb gets wrong.
Records behind each entry
Sorted by how much evidence exists, not by how likely you are to meet one. The peak month is the effort-adjusted figure, and it is left blank wherever the sample is too thin for the month-to-month wobble to mean anything.
| Entry | Accepted name | Rank | GBIF records | Research-grade | Half fall in | Peak, adjusted | Most reported from |
|---|---|---|---|---|---|---|---|
| Norway maple | Acer platanoides L. | species | 1,034,483 | 145,657 | Apr–Jul | June | Germany |
| Norway spruce | Picea abies (L.) H.Karst. | species | 1,007,278 | 91,765 | Jun–Aug | July | Sweden |
| Black locust | Robinia pseudoacacia L. | species | 496,561 | 137,923 | Apr–Jul | May | France |
| Black cherry | Prunus serotina Ehrh. | species | 288,858 | 135,083 | Apr–Jul | May | the Netherlands |
| Boxelder | Acer negundo L. | species | 254,110 | — | Mar–Jun | April | the United States |
| Northern red oak | Quercus rubra L. | species | 226,793 | 123,423 | May–Aug | November | the United States |
| Douglas fir | Pseudotsuga menziesii (Mirb.) Franco | species | 164,367 | 89,698 | Mar–Jul | February | the United States |
| Pin oak | Quercus palustris Münchh. | species | 147,819 | 31,019 | Aug–Oct | December | the United States |
| Honey locust | Gleditsia triacanthos L. | species | 139,443 | 77,965 | Mar–Jul | February | the United States |
| Red maple | Acer rubrum L. | species | 133,130 | 162,550 | Mar–Jul | October | the United States |
| Eastern white pine | Pinus strobus L. | species | 115,039 | 140,642 | Mar–Jul | February | the United States |
| Sweetgum | Liquidambar styraciflua L. | species | 97,409 | 116,114 | Mar–Jul | December | the United States |
| Silver maple | Acer saccharinum L. | species | 95,335 | 63,212 | May–Aug | October | the United States |
| American beech | Fagus grandifolia Ehrh. | species | 90,676 | 123,876 | Mar–Jul | February | the United States |
| Tulip tree | Liriodendron tulipifera L. | species | 77,205 | 105,618 | Apr–Jun | April | the United States |
| Eastern redcedar and arborvitae | Juniperus virginiana L. | species | 71,990 | 122,953 | Jan–Jun | February | the United States |
| Eastern hemlock | Tsuga canadensis (L.) Carrière | species | 64,784 | 82,747 | Mar–Jul | February | the United States |
| Eastern redbud | Cercis canadensis L. | species | 64,693 | 111,805 | Mar–May | March | the United States |
| Sassafras | Sassafras albidum (Nutt.) Nees | species | 62,820 | 75,951 | Apr–Jul | May | the United States |
| Quaking aspen | Populus tremuloides Michx. | species | 61,907 | 80,099 | Jun–Aug | June | the United States |
| Ginkgo | Ginkgo biloba L. | species | 60,681 | 46,232 | Jun–Sep | November | the United States |
| Sugar maple | Acer saccharum Marshall | species | 59,528 | 116,271 | May–Aug | October | the United States |
| American basswood | Tilia americana L. | species | 59,524 | 68,625 | May–Aug | October | the United States |
| American sycamore | Platanus occidentalis L. | species | 50,035 | 96,662 | Feb–Jul | February | the United States |
| White oak | Quercus alba L. | species | 47,555 | 83,064 | Apr–Aug | December | the United States |
| American elm | Ulmus americana L. | species | 45,426 | 78,701 | Mar–Jul | March | the United States |
| Bald cypress | Taxodium distichum (L.) Rich. | species | 43,257 | 64,368 | Apr–Aug | November | the United States |
| Flowering dogwood | Cornus florida L. | species | 42,748 | 70,421 | Apr–May | April | the United States |
| Black walnut | Juglans nigra L. | species | 39,932 | 85,701 | May–Aug | October | the United States |
| Balsam fir | Abies balsamea (L.) Mill. | species | 39,062 | 48,080 | May–Aug | February | Canada |
| Eastern cottonwood | Populus deltoides W.Bartram ex Marshall | species | 36,424 | 64,817 | Apr–Jul | April | the United States |
| Paper birch | Betula papyrifera Marshall | species | 28,894 | 51,283 | Mar–Jul | February | Canada |
| Osage orange | Maclura pomifera (Raf. ex Sarg.) C.K.Schneid. | species | 28,756 | 36,925 | Jul–Oct | November | the United States |
| Hackberry | Celtis occidentalis L. | species | 28,574 | 47,957 | May–Aug | October | the United States |
| Southern magnolia | Magnolia grandiflora L. | species | 19,648 | 68,742 | Jan–May | February | the United States |
| Shagbark hickory | Carya ovata (Mill.) K.Koch | species | 17,910 | 41,288 | Mar–Jul | February | the United States |
| White ash | Fraxinus americana L. | species | 17,819 | 66,604 | May–Aug | September | the United States |
| Black willow | Salix nigra Marshall | species | 16,544 | 31,183 | Mar–Jun | April | the United States |
| Red pine and Scots pine | Pinus resinosa Aiton | species | 12,319 | 26,645 | Apr–Aug | February | the United States |
| Live oak | Quercus virginiana Mill. | species | 9,706 | 38,577 | Jan–Jun | December | the United States |
| Northern catalpa | Catalpa speciosa (Warder ex Barney) Warder ex Engelm. | species | 9,623 | 33,647 | May–Jul | June | the United States |
| Red mulberry | Morus rubra L. | species | 9,368 | 23,880 | Apr–Jun | April | the United States |
| Horse chestnut and buckeye | Aesculus L. | genus | 429,086 | 226,651 | Apr–Jun | April | the United Kingdom |
This table is assembled from open data and is free to reuse with a link back to this page. The snapshot behind every Orvik key is published as one downloadable file on the open field data page, with each source's licence terms.
Questions people ask about this
How do I tell if leaves are opposite or alternate?
Look at where the leaf stalks meet the twig. If two leaves join at the same point on opposite sides, it is opposite; if they stagger up the twig one at a time, it is alternate. Check a healthy shoot rather than a stressed twig, and use buds instead of leaves in winter. In eastern North America the opposite-leaved trees are essentially maple, ash, dogwood, horse chestnut, catalpa and the viburnum family — everything else is alternate.
Is this one leaf or several?
Find the bud. There is always a bud in the angle where a true leaf meets the twig, and never one where a leaflet meets the leaf stalk. Compound leaves also drop as a single unit in autumn. Getting this wrong is the most common beginner error, because it makes a walnut or an ash look like a twig full of small opposite leaves.
How do I tell a white oak from a red oak?
Look at the tips of the lobes. White oak group leaves have rounded lobes with no bristle; red oak group leaves have pointed lobes ending in a fine bristle. The acorns confirm it: white oaks mature in one season and have a hairless cup interior, red oaks take two seasons and have a hairy cup.
What tree has leaves shaped like a mitten?
Sassafras and mulberry both produce unlobed, mitten and three-lobed leaves on the same branch. Sassafras has smooth leaf edges and smells strongly of root beer when crushed; mulberry has coarsely toothed edges and bleeds milky sap from a torn stalk. Both are alternate and both grow in disturbed ground, so the smell and the sap are what separate them.
How do I tell a spruce from a fir from a pine?
Pines hold their needles in bundles of two, three or five wrapped in a papery sheath. Spruces and firs have single needles. A spruce needle is four-sided and rolls between your fingers, and leaves a rough peg on the twig; a fir needle is flat, will not roll, has two white stripes underneath and leaves a smooth round scar. Fir cones stand upright and fall apart on the tree; spruce cones hang down and drop whole.
Why do leaves on the same tree look different?
Sun and shade change leaf size, thickness and lobing considerably, so a leaf from a shaded interior branch can look like a different species from one in the crown. Juvenile shoots, stump sprouts and water sprouts are frequently atypical too. Take three leaves from a normal branch on a healthy part of the tree before you decide.
Can an app identify a tree from one leaf photo?
Often, and it is much more reliable if you give it more than the leaf. Photograph the leaf flat with something for scale, the underside, a twig showing two nodes so the arrangement is visible, and the bark or any fruit. Then check the suggestion against this key using the arrangement and compound tests, which are the two characters a photograph most often gets wrong.
Still not sure? Point a camera at it
A filter narrows trees down to a shortlist. Orvik reads the photo itself and names the species, with the look-alikes ranked underneath so you can check the call yourself.