Plant of the Week

Streambank Wild Hollyhock (Iliamna rivularis) (Dougl. Ex Hook.) Greene

By Teresa Prendusi

Map of the United States showing states. States are colored green where Streambank Wild Hollyhock may be found.
Range map of Streambank Wild Hollyhock. States are colored green where the species may be found.

Streambank Wild Hollyhock.
Iliamna rivularis, Tony Grove, Utah. Photo by Teresa Prendusi.

Wild hollyhock is a large perennial forb belonging to the "mallow" or Malvaceae family. This stunning species has 24-80 inch stems with large showy white to pink flowers growing in a loose terminal cluster (raceme). Iliamna rivularis is found in open forested slopes, meadows, and disturbed areas, in a variety of plant communities between 7,000 – 11,000 feet. The species name "rivularis" refers to its site characteristic of often being found along streamsides.

Wild hollyhock is a shade-intolerant plant, which flowers very profusely following disturbances such as wildfire. It quickly is eliminated from post-fire communities, however, once it becomes overtopped by other vegetation. Germination takes place in full sun and seeds can remain dormant viable for more than a century.

Wild hollyhock is highly preferred by livestock, as well as elk and mule deer and other wildlife in recently burned habitats.

For More Information: PLANTS Profile - Iliamna rivularis, Streambank Wild Hollyhock

wild hollyhock growing along a streambank.
Streambank Wild Hollyhock (Iliamna rivularis). Forest Service Region 4 file photo.

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