Nectar guide
Markings that direct a pollinator to the reward, frequently in ultraviolet and invisible to us.
Botany · also called honey guide, UV guide
Definition
Bees see ultraviolet, blue and green, and cannot see red as a distinct colour. Many flowers that look plain to us carry ultraviolet bullseyes and lines pointing at the nectaries. Several also change their guide colour once pollinated and stop producing nectar — horse chestnut's turns yellow to red, lungwort pink to blue, forget-me-not's eye yellow to white — and bees learn the signal and skip the changed flowers.
Where the word gets used loosely
Red flowers are usually signalling to birds rather than bees. Where bees visit them they are following ultraviolet patterns rather than the colour we see.
Plant records that discuss this
See also
Other botany terms
Sources
Sources
- Field Guide to the Bees of Great Britain and Ireland — Bloomsbury (2015) · Field guide
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