have you listened to them? their lyrics are crammed with nature references and they sound like intensely sunny summer days to me.
i think there are enough cockrock posters in the world nor could i improve upon that style, so i went in another direction. there was NO WAY i was putting a wolf on a poster for wolfmother, it's been done. aside from that, i don't tend to build images on direct literal references, i prefer to take a step or two away from that. in this case, i based the bright ass yellow on their sound.