Cedar

Dry, clean and woody, with that unmistakable sharpened-pencil quality. Cedar is the least sweet of the common woods and the most structural — it gives a blend a spine.

There are two main kinds and they do not smell alike. Virginian cedarwood is the pencil one: crisp, dry, a little peppery. Atlas cedar is softer and smokier, closer to a fire that has gone out than to a workshop.

It sits between the heart and the base, which makes it one of the more reliable notes in a diffused blend — present for most of the evening without ever dominating. It also does well in rooms where something sweeter would feel cloying: offices, hallways, anywhere that needs to smell clean rather than cosy.