Is Plaid Cymru's official colour green or yellow?

Plaid's emblem is a yellow-and-orange "poppy", which normally appears on a background of green, which was the party's traditional colour.

The party defines precise shades of "Plaid green, Plaid yellow, Plaid orange, and Plaid grey" for use in its publicity material.

Yellow-on-green is the most commonly seen colour combination.