How to prune pompas grass surrounded by trickle? I have 2 full-size pompass grass plants(plumes 7-8ft) and I need to...

I have 2 full-size pompass grass plants(plumes 7-8ft) and I need to know how short to cut them hindmost. I am in Tn. and we are nearly to get into the winter weather.
I enjoy a plant looks almost close to...
Leave them til Spring. Then cut them back to in the region of 6" - 8" in April or May in the past the new green starts coming out.

Burying Fig Trees?
Leave them high through the winter - it helps protect the crowns. Also make available you something to look at for winter interest.

Cut them back surrounded by the spring.
How can I decimate the Poison Ivy plant?
Answers:    This cooperation looks like it might hold some info you're looking for:

http://pubs.caes.uga.edu/caespubs/hortic...

"Before growth begins within the spring, prune away any brown leaves and dead materials that accumulate at the base of plants."