Lyme Grass

COMMON NAME: LYME GRASS
ALTERNATIVE NAMES: Blue Dune Lyme Grass, Sand Rye Grass, Wild Rye, and
Blue Lyme Grass.
SCIENTIFIC NAME: Leymus arenarius; Elymus arenarius
FAMILY: Poaceae
ORIGIN: Northern Europe
K. Peters
US INTRODUCTION: Introduced for ornamental purposes. Lyme Grass is now
present throughout the Great Lakes region. Specifically in Illinois, Lyme Grass has
been documented in Cook, Kane, and Lake County.
Lyme Grass
MAJOR PATHWAYS OF SPREAD:
• Ornamental use
• Underground stems (rhizomes)
• Seed dispersion by various sources
• Fast growing and long lived (~10 years)
IDENTIFICATION CHARACTERISTICS:
• 32 inches tall and 3 feet wide at maturity
• Leaves are blue/green and grow about 12 inches along and ½ inch wide
• Flowers are blue/green dense spikes during the summer, and turn beige later in
the year
• The ideal habitat for Lyme Grass is full sun to partial shade. It is very adaptable
to both dry and moist locations, and is also considered to be drought-tolerant.
Lyme grass can grow in a number of soil types or pH levels, and is able to
handle environmental salt. Lyme Grass is very tolerant, and is even able to
tolerate urban pollution and is able to thrive in inner city environments.
K. Peters
Lyme Grass Spikes
• Grows in soggy thickets and meadows, fens, and roadside ditches
NATIVE LOOK-ALIKES:
• Marram Grass (Ammophila breviligulata): Leaves are distinctly green, not blue/green like in Lyme Grass.
• Streambank Wheat Grass (Elymus lanceolatus): Lyme Grass and Streambank Wheat Grass are very similar in appearance. If the
plants are fertile, one can see that Leymus arenarius spikes (flowers) are 15-25 mm thick and the spikes of Elymus lanceolatus are
only 5-10 mm thick. Additionally, the leaves in Elymus lanceolatus are thinner than that of Leymus arenarius appear to be hairy, and
are parallel veined. The flower cluster is longer than it is broad.
Halley
Marram Grass
Royalbroil
Marram Grass
W. Alverson
Streambank Wheat Grass
ADDITIONAL RESOURCES:
University of Wisconsin Green Bay - Cofrin Center for Biodiversity
http://www.uwgb.edu/biodiversity/herbarium/invasive_species/leyare01.htm
www.NewInvaders.org