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Common reed is an aggressive grass that is considered invasive in many areas therefore it is not recommended. Common reed (Phragmites australis) is found worldwide and is comprised of two subspecies. There is a native subspecies (P. australis subsp. americanus) and a non-native subspecies (P. australis subsp. australis). While the nonnative subspecies has become a problem in many areas, the native subspecies plays an important role in wetland habitats and should be conserved. The native subspecies has a wide native range, but it is relatively uncommon in some areas. There are some visual differences between the two subspecies:

Nonnative:   Green or tan stems are covered by tightly clinging leaf sheaths.  The foliage is blue green.  This plant forms dense colonies and may grow as tall as 20 feet.  The flower clusters/seed heads are usually larger and more dense than the native.

Native: Lower leaf sheaths fall off and exposed stem turns red in sunlight.  The foliage is yellow green. This plant grows more as scattered stems and is usually shorter (6 to 8 feet) than the nonnative.  Flower cluster/seed heads are usually smaller and more open than the nonnative.

The rest of this page will concern only the nonnative species which is a plant of concern and considered invasive in many areas.

  • Family (English) Grass
  • Family (botanic) Poaceae
  • Tree or plant type Grass
  • Native locale Non-native
  • Size range Large plant (more than 24 inches)
  • Light exposure Full sun (6 hrs direct light daily)
  • Hardiness zones Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8, Zone 9, Zone 10
  • Soil preference Wet soil
  • Tolerances Alkaline soil, clay soil, Occasional flooding, Road salt, Wet sites
  • Flower color and fragrance Purple
  • Shape or form Upright
  • Growth rate Fast

Size and form:

Common reed is an aggressive spreader and can form large colonies that crowd out native plants. It can grow up to 20 feet tall.

Native geographic location and habitat:

World wide distribution.

Leaf description:

The leaves, which are held on thick stems, are somewhat blue-green in color and 1/2 to 1 inch wide and up to 1 foot long. The green or tan stems are covered by tightly clinging leaf sheaths.

Flower description:

Flowering occurs in late summer. Tiny flowers are in upright, dense clusters. They have a purplish cast to them.

Fruit, cone, nut, and seed descriptions:

The small fruit (caryopsis or grains) form along the dense clusters that held the flowers and are beige or brown in color.


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