(Iris virginica var. shrevei)
Conservation • Wetland • Description • Habitat • Ecology • Use • Distribution • Taxonomy
Description |
Southern blue flag is a 20″ to 40″ tall, erect, perennial forb that rises on a single stem from a thick, creeping, freely-branching rhizome and fleshy roots. It often forms dense clumps. The stems are erect to arching and usually have 2 or 3 branches. They seldom fall over after flowering. They are shorter than the leaves so that the leaves rise above the flowers. Basal leaves are narrowly sword-shaped, green to grayish-green, 23½″ to 31½″ long, and 1″ to 1 3 ⁄16″ wide. They are erect and commonly arching near the top. There are 1 or 2 leaves on the stem subtending each branch. Stem leaves are similar to the basal leaves but shorter. The inflorescence is 2 or 3 flowers at the end of the stem and 1 or 2 flowers at the end of the branch. The cluster emerges from an enveloping pair of large bracts (spathes). The flowers are 3″ to 3½″ wide. There are 3 petals and 3 petal-like sepals, all of which are fused at the base into a ⅜″ to ¾″ long tube. Each sepal is egg-shaped to oval, widely spreading, arched, 1½″ to 2¾″ long, and ¾″ to 1½″ wide. It is abruptly or gradually narrowed toward the base (clawed) and broadly expanded toward the tip. It is pale blue to purple near the tip quickly fading to white with darker blue or purple veins toward the middle. There is a bright yellow patch near the throat. The claw is green in the center, surrounded by bright yellow, with purple veins. What appears to be an upper lip is actually a branch of the style. The highly modified style is enlarged and divided into 3 branches. Each petal-like style branch covers the lower portion of a one sepal, extending just beyond the narrowed claw and concealing the stamens. The style branch is 1 3 ⁄16″ to 1⅜″ long, distinctly ridged, and flared at the tip. It does not have ear-like lobes at the base. The 3 petals are smaller than the sepals. They are lance-shaped to spatula-shaped, erect, 1¼″ to 2¾″ long, and ⅜″ to 1¼″ wide. They are often notched at the tip. The flowers last 1 to 4 days and are somewhat fragrant. All white flowers are found, though rarely. The fruit is a green, elliptical to egg-shaped, three-sided, 1¼″ to 2⅜″ long, ⅜″ to ¾″ in diameter capsule. It is rounded-triangular in cross section. |
Height |
20″ to 40″ |
Flower Color |
Lavender to violet |
Similar Species |
Northern blue flag (Iris versicolor) top of the stem is equal to or higher than the leaves. The sepals and petals are darker in color, violet blue. The patch at the base of the sepals is yellowish-green, not bright yellow. The 3 petals are not notched at the tip. |
Habitat |
Wet. Meadows, swamps, marshes, and streambanks. In water less than 40″ deep. Full to partial sun. |
Ecology |
Flowering |
May to July |
Pests and Diseases |
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Use |
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Distribution |
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Sources |
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5/20/2023 | ||
Nativity |
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Native |
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Occurrence |
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Common |
Taxonomy |
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Kingdom |
Plantae (green algae and land plants) |
Subkingdom |
Viridiplantae (green plants) |
Infrakingdom |
Streptophyta (land plants and green algae) |
Superdivision |
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Division |
Tracheophyta (vascular plants) |
Subdivision |
Spermatophytina (seed plants) / Angiospermae (flowering plants) |
Class |
Liliopsida (monocots) |
Order |
Asparagales (agaves, orchids, irises, and allies) |
Family |
Iridaceae (irises and allies) |
Subfamily |
Iridoideae |
Tribe |
Irideae |
Genus |
Iris (irises) |
Subgenus |
Limniris |
Section |
Limniris |
Series |
Laevigatae |
Species |
southern blue flag (Iris virginica) |
Subordinate Taxa |
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Synonyms |
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Iris shrevei Iris versicolor var. blandescens Iris versicolor var. shrevei |
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Common Names |
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Shreve’s iris southern blue flag southern blueflag Virginia blue flag |
Glossary
Bract
Modified leaf at the base of a flower stalk, flower cluster, or inflorescence.
Claw
A stalk-like narrowed base of some petals and sepals.
Linear
Long, straight, and narrow, with more or less parallel sides, like a blade of grass.
Rhizome
A horizontal, usually underground stem. It serves as a reproductive structure, producing roots below and shoots above at the nodes.
Sepal
An outer floral leaf, usually green but sometimes colored, at the base of a flower.
Spathe
One or two large bracts that subtend, hood, or sometimes envelope a flower or flower cluster, as with a Jack-in-the-Pulpit.
Visitor Photos |
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Kirk Nelson |
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Southern blue flag iris, on the shore of Pickerel Lake |
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Found on the shore of Pickerel Lake |
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MinnesotaSeasons.com Photos |
Plant |
Inflorescence | |
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Flower |
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Slideshows |
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Other Videos |
blue flag (Iris virginica) |
About
Uploaded on May 19, 2010 Aquatic and Invasive Plant Identification Series by the UF/IFAS Center for Aquatic and Invasive Plants ( http://plants.ifas.ufl.edu ) and the Florida Fish and Wildlife Commission, Invasive Plant Management Section. For more information about blue flag, go to http://plants.ifas.ufl.edu/node/206 Video editor/videographer - Phil Chiocchio |
Southern Blue Flag Iris |
About
Published on Jun 28, 2012 Wild Iris (Iris virginica) in wetland restoration near Ridgetown, Ontario |
Visitor Sightings |
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Kirk Nelson 5/31/2019 |
Location: Mississippi National River and Recreation Area - Coldwater Spring |
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Kirk Nelson 6/2/2017 |
Location: Lilydale Regional Park Southern blue flag iris, on the shore of Pickerel Lake |
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Kirk Nelson 6/13/2014 |
Location: Lilydale Regional Park Found on the shore of Pickerel Lake |
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MinnesotaSeasons.com Sightings |
Created: Last Updated: © MinnesotaSeasons.com. All rights reserved. |