Yellow Flag Iris
Alongside slow moving rivers and on the edges of lakes in shallow water or mud
Native to Europe, Great Britain and North Africa; occurs as a non-native throughout much of the US and in other countries
No listed status
This species is
to the Truckee Meadows.
Yellow flag iris is an aquatic plant that grows 2 to 3 feet tall with long, flat, sword-like leaves which are a deep green color. Several 2.5 to 3.5 inch flowers atop the end of stems and are pale to bright yellow and can have brownish-purple speckles.
Yellow flag iris is poisonous to livestock and contact with resin can lead to skin irritation in humans.
This plant reproduces by both seeds and rhizomes, an underground plant stem that puts out roots and shoots and allows the plant to spread easily when small pieces break off.
Hundreds of yellow flag iris plants can be connected by rhizomes.
Yellow flag iris can form dense monoculture that invades native aquatic plants and can diminish habitat for native fish and birds.
Washington State Noxious Weed Control Board,Yellow Flag Iris, 2002. https://www.nwcb.wa.gov/weeds/yellow-flag-iris
New York Invasive Species Information, Yellow Flag Iris, 2019. http://nyis.info/invasive_species/yellow-flag-iris/
Image: Plant Right, https://www.flickr.com/photos/149372353@N02/33325662490/, license https://creativecommons.org/licenses/by/2.0/, cropped from original.
Image: Mike Prince, https://www.flickr.com/photos/mikeprince/32423548047/, license https://creativecommons.org/licenses/by/2.0/, cropped from original.
Image: Liam Lysaght, https://www.flickr.com/photos/30802095@N04/27656631413/, license https://creativecommons.org/licenses/by/2.0/, cropped from original.
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