purple loosestrife
Lythrum salicaria L.


Overview


Appearance
Lythrum salicaria is a tall, multistemmed (30-50 per plant), perennial forb that can grow up to 10 ft. (3 m) in height.
Foliage
The opposite or whorled leaves are dark-green, lance-shaped, sessile, 1.5-4 in. (3.8-10.2 cm) long and round or heart-shaped at the base.
Flowers
Flowering occurs in July to October, when pink to purplish flowers develop in 4-16 in. (10.2-40.6 cm) long spikes at the tops of the stems. Flowers have 5-7 petals and twice as many stamens as petals.
Fruit
Fruits are capsules that are enclosed in the hairy sepals and contain several reddish brown seeds.
Ecological Threat
Lythrum salicaria is a serious invader of many types of wetlands, including wet meadows, prairie potholes, river and stream banks, lake shores, tidal and nontidal marshes, and ditches. It can quickly form dense stands that completely dominate the area excluding native vegetation. This plant can spread very rapidly due to its prolific seed production; each plant can produce up to 2.5 million seeds per year. It can also hybridize with native loosestrife species, potentially depleting the native species gene pool. Lythrum salicaria is native to Europe and Asia. It was first introduced into North America in the early 1800s for ornamental and medicinal purposes.

Resources


Selected Images



Maps



EDDMapS Distribution

EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit www.eddmaps.org

State Regulated List

State Regulated List - This map identifies those states that list this species on their regulated list. For more information, visit Invasive.org

State Regulated List
Legend
   No Data for this state
   Troublesome or Common weed in one or more crops

Most Troublesome / Most Common Agricultural Weed List
This map identifies those states that consider this species either most troublesome or most common in at least one commodity. For more information, visit the MTMC project page.

Invasive Listing Sources


Taxonomic Rank


Kingdom: Plantae
Phylum: Magnoliophyta
Class: Magnoliopsida
Subclass: Rosidae
Order: Myrtales
Family: Lythraceae
Genus: Lythrum
Subject: Lythrum salicaria L.

Synonyms and Other Names


Other Common Names:
purple lythrum, rainbow weed, salicaire, spiked loosestrife

Categories


Plants - Aquatic Plants