Assertion: iris's stem | /r/HasProperty | underground
Facets:
Source sentences:
text: Irises are either bulbous or rhizomatous (with thick, creeping underground stems) and have six petallike floral segments, the more erect inner ones called standards and the usually drooping outer ones called falls.
text: It grows 3 to 6 inches tall and produces underground stems that spread horizontally and shallowly.