Stem has cross walls below flower heads

Stem has cross walls below flower heads.

• Left: flower heads are globe-shaped with fewer than 30 flowers, and bristly leaves. Juncus brachycarpus.  [PDF 301 KB]
• Right: flower heads have fewer than 30 flowers, and leaves are not bristly. 

[Larry Allain, USGS, Wetland & Aquatic Research Center / Trevor James, AgResearch]