Reading buds on a bare twig

A bare twig in winter carries much of the information needed to name a tree. The buds are set in a fixed pattern, and that pattern is usually the first thing to check. The method below takes a few minutes and needs no tools beyond a hand lens and a clear view of the branch.

Opposite or alternate

Buds on most broadleaf trees sit in one of two arrangements. Opposite buds come in pairs, one on each side of the twig, at the same height. Alternate buds come one at a time, each on the side opposite the one below, so that the twig looks staggered. Many trees keep the same arrangement through their life, so a clear answer is a useful clue.

Opposite: A pair of buds facing each other across the twig, with one bud on each side at the same level.
Alternate: Single buds set on alternate sides, rising in a spiral up the twig.
Terminal bud: The bud at the tip, which may be larger than the side buds and is often a different colour.

Steps

Choose a twig from a low branch that you can see clearly, and look at it from a few paces away.
Find the tip and note whether there is a terminal bud, and its size and colour.
Work down the twig and check three pairs or singles of buds. Ask whether each pair faces the other across the stem.
If the buds are single, note which side each one sits on, and whether the sides alternate.
Check the bud scales: are they dark, pale, sticky or hairy?
Compare what you see with the table in the relevant entry before deciding.

What it suggests

Opposite buds with a black terminal bud point towards common ash. Opposite buds with a plump, green-brown terminal bud point towards sycamore or another maple. Small, pointed, reddish-brown buds set alternately point towards silver birch or a related birch. Each reading narrows the field and is not a final answer, so check the bark and leaves as well.

Repeat the method on a second twig from another part of the same tree. Buds on one tree usually follow one pattern, so a second check helps confirm the first.