This page is dedicated to showing the many different types and forms of
iris rhizomes. With bulbous irises being an exception, all irises have
some form of a rhizome. Some are quite obvious, as is the case with
Bearded irises; others looks like any other massed perennial roots, but
on a closer looks shows the rhizome.

Tall
Bearded rhizome

Tall Bearded rhizome
And a few bulbs....
Iris
barbatula bulb
Iris bucharica bulb