Budworm - Pest and Pollinator

 Some type of budworm on a calendula flower.  

How do I know it's a budworm?

Here's the hole the newly hatched larvae chewed in the bud.  Budworms eat the flower from the inside out.  They are a type of cutworm, not a worm of course, but the larvae of a moth.  After hatching from an egg laid on the plant, it chews its way into the bud, growing from about 1/16" to about 2".    

Another sign is the frass (larvae poop) on the stem. 

Budworms are sometimes called geranium budworms, or tobacco budworms, but there are types that are destructive pest to conifers.  Some are a serious pest for the southern US tobacco and cotton growers.  I don't know which kind this is, and didn't see the parent moth.  The moths don't really have their own name, they are just called adult budworm moths.  

This one was gone the next time I checked (of course I left it, it's just one late season calendula flower!).  Maybe a bird ate it, or it could have reached its full size, dropped to the ground, where it will pupate in the soil to emerge as a moth.  The larvae only feed for about a month, and there may be two generations a year.  The moths feed on nectar, so they are considered pollinators.