[The Iris Family East of the Cascade Mts. of Oregon and Washington]
Pale Yellow Iris, Yellow Flag, Yellow Water Iris
Iris pseudacorus
Yellow flag as seen along the Little Spokane River downstream of Picture Rocks, Little Sokane River Natural Area........June 19, 2009.
Characteristics:
Yellow flag is a non-native perennial with thick rhizomes from
which arise thick, stiff leaves enfolding each other at the base. Plants typically
arise as much as 1 meter in height. The leaf blades are as much as 50-90 cm
long and 20-35 mm wide and taper to a point at the tip. The leaves are often
blue-green in color and the middle leaves are the longest.
The several yellow flowers are found at the apex of the stem.
They are large and showy, often with fine purple markings.
Habitat:
Yellow flag is common around streambanks and along the margins
of ponds and lakes. It is generally found in areas with permanent shallow water,
and at depths less than 0.5 meters.
Range:
An introduced species from Europe, yellow flag may be found
within its habitat over much of North America.
Use:
Yellow flag is a pretty, introduced iris
for gardens with moist soils or ponds! Be aware that if you have planted it
next to a stream, it will spread from your property onto adjacent streambanks
where it crowds out native riparian plants.
It has value as a species for sediment retention and shoreline
stabilization. The thick stands of yellow flag provide hiding spots for wildlife.
A close-up of the flower of yellow flag as seen along the Little Spokane River downstream of Picture Rocks, Little Sokane River Natural Area.........June 19, 2009.
A view of the habitat of yellow flag as seen along the Little Spokane River downstream of Picture Rocks, Little Sokane River Natural Area..........June 19, 2009.
Yellow water iris growing in shallow water in side channels to the Little Spokane River, Little Spokane River Natural Area..........May 23, 2010.
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Yellow water iris blooming (left) in shallow water in side channels to the Little Spokane River, Little Spokane River Natural Area.........June 9, 2013. The photo at right shows yellow water iris as seen in shallow backwaters of the Little Spokane River about a quarter mile upstream from North Nine Mile Drive, Little Spokane River Natural Area.........May 9, 2016.
Paul Slichter