Identify Tree Species: Needles, Leaves, Bark and Fruit

To identify a tree species, answer one question first: does it carry needles or scales, or broad flat leaves? Virginia Tech's dendrology primer puts this first because it divides trees into conifers and broadleaves, and every later step depends on which side you are on. Most conifers carry needles; cedars carry overlapping scales instead.

The Arbor Day Foundation's online key works the same way. You pick your region and then answer step-by-step questions about the leaves, and its companion tree guide covers more than 200 trees and shrubs. The University of Wisconsin Extension points readers to the same key for trees across the US, and to state herbarium keys for native species; Wisconsin alone has more than 60 native tree species.

After that first split, work through the tree in this order:

• Leaves or needles — how they are grouped and attached
• Branching — opposite pairs or staggered
• Bark — on the trunk of a full-grown tree
• Fruit, cones and buds — including what has fallen on the ground

Look at how the needles leave the twig. Virginia Tech notes that pines grow needles in bundles, called fascicles, while spruces, firs and hemlocks grow single needles, and cedar leaves grow as scales.

Bundle size then narrows the pines. University of Wisconsin Extension gives five needles per bundle for white pine and two for red pine and jack pine.

For single needles, University of Wisconsin Extension offers a test you can do with one hand: spruce needles are sharp and can be rolled between your fingers, while fir needles are flat with softer tips and will not roll. Its horticulture service adds that both carry much shorter needles than pines.

Check the twig before the leaf. University of Wisconsin Extension lists maples, ashes, viburnums and most dogwoods as opposite-branched, with nearly all other broadleaf species alternate. A matched pair of buds or leaves therefore removes most candidates at once.

Next, decide whether the leaf is simple or compound. Virginia Tech defines a simple leaf as one blade and a compound leaf as several to many leaflets on one leaf. Many beginners photograph a single leaflet and get the wrong tree; trace the stalk back to the bud first. Our tree leaf identification guide walks through margins, lobes and veins after that.

A worked example from Michigan State University Extension's key shows how quickly this narrows: an alternate-branched tree with compound leaves of 9 to 15 leaflets and chambered pith inside the twig is black walnut; an opposite-branched tree with 5 to 9 leaflets is an ash; opposite with 3 to 5 leaflets is boxelder.

Leaves alone often leave two or three candidates. University of Wisconsin Extension points to bark, buds and fruit as the tie-breakers: paper birch has white peeling bark, shagbark hickory has thick curling strips, and fruits and cones differ sharply between species.

• Bark — judge a mature trunk at chest height; see tree bark identification
• Fruit and cones — acorns, winged samaras, husked nuts and cones often lie under the tree well into winter
• Buds — in winter, bud shape and leaf scars carry much of the identification, for example on ash

For common groups, the dedicated guides go further: oak, maple and elm.

A photo identification is fastest, but it is only as good as what the photo shows. University of Wisconsin Extension warns that apps are often incorrect, especially for understory plants, and that in 2025 the most popular apps ranged from 30% to 80% accurate. The i-Tree project, which lists several apps and web keys, likewise says accuracy depends on the quality of what you give the tool and that it endorses none of them.

Take four photos instead of one, so the tool and you can check each other:

• A leaf still attached to its twig, showing whether leaves are paired or staggered
• The whole leaf, from the stalk to the tip, so leaflets are counted correctly
• The trunk at chest height, straight on, in even light
• Fruit, cones or buds, including anything on the ground below

Then check the suggested species against the features above. If the app's answer is an opposite-branched tree and your twig is alternate, the answer is wrong, however confident it looks.