Lyme Grass

(Leymus arenarius or Elymus arenarius)

An invasive grass in coastal regions. Its form of fast vegetative growth can negatively affect native beach and dune vegetation. As Lake Michigan's water levels have gone down, more areas have been colonized by this species. Stems are smooth, round and stout; the plant is 2-4’ tall.

Other names for this plant include:

  • Common names: Sand ryegrass
  • Scientific names: Elymus arenarius

Ecological threat:

  • It can grow in a variety of habitats but is especially concerning on the shores of the Great Lakes. With a spreading root system, lyme grass can stabilize our naturally shifting dunes and compete with rare grasses.
  • Occupies the same dune habitat and poses a threat to several native rare plants which include: Elytrigia dasystachya, Calamovilfa longifolia, Salix cordata, Cirsium pitcheri, Solidago simplex, Cakile lacustris, and Euphorbia polygonifolia.
European Frogbit

European Frogbit

(Hydrocharis morsus-ranae)


(Lysimachia nummularia or L. nummelaria)