Purple Loosestrife

 

Common name: Purple Loosestrife (purple lythrum, spiked loosestrife)

 

Growth form: Forb

 

Life Span: Perennial

 

Origin: Eurasia and Africa

 

Flowering Dates: July-September

 

Reproduction: Rhizomes and seeds

 

 

Height: 0.4 - 2.5 m (1.3 - 8 ft.)

 

Flower: Rose - purple corolla (up to 2 cm across), petals 6 (5 - 7), crinkled; tube cylindrical (4 - 6 mm long), greenish; calyx lobes 6; stamens 12

 

Fruit: Capsule (4 - 7 mm in diameter), 2 - celled, many - seeded

 

Seed: Ovoid (1 mm long or less)

 

Leaves: Opposite or in whorls; blades simple, lanceolate (2 - 11 cm long, 5 - 15 mm wide), tip sharply pointed, base rounded or heart - shaped, margins entire, surfaces pubescent; sessile

 

Stems: Erect, 4 - angled, hairless to pubescent, not highly branched, usually from a woody base

 

Underground: Rhizomes, short; taproot

 

Scattered across Nebraska in marshes, along rivers, ditches, and wet meadows. The largest infestations are along the Platte River in central Nebraska and along the Missouri River above Gavins Point Dam

 

Uses and Values: Purple loosestrife is an escaped ornamental. It is an excellent honey plant

 

Poisoning: None

 

Other: Purple loosestrife is rapidly and aggressively spreading and has been placed on the noxious weed list in some north central states. Several varieties have been developed which can cross with wild types and produce viable seed. It is extremely difficult to control, and concentrated efforts should be made to keep it from spreading

 

Similar Species: Winged loosestrife (Lythrum alatum Pursh) and California loosestrife (Lythrum californicum T. & G.) are native species similar in appearance. They differ from purple loosestrife by having solitary or paired flowers in the leaf axils rather than many flowers in terminal spikes and 6 - 8 stamens rather than 12. Winged loosestrife leaves are gray - green and often somewhat fleshy. California loosestrife has green, membranaceous leaves.