Pattern help

[Elizabeth262]

I’ve never used chenille stems before on crocheting, I’m having some trouble with this pattern that requires chenille stems. Here is the pattern:

Please help!

[Granny Square]

I am going to guess that a 'white chenille stem' means pipe cleaner, like this

You are going to sc over the stem into 20 chains in the usual way, THEN bend the stem under the chain, turn the chain upside down, and repeat (except with HDC not SC), using the unused loops of the chain, back to the beginning.  So this gives you a double-thick wire-reinforced stem (or spine? for a feather).