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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 world wide 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 non-native 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, it is relatively uncommon in some areas. There are some visual differences between the two subspecies:

Non-Native:   Green or tan stems covered by tightly clinging leaf sheaths; blue green foliage, forms dense colonies and may grow as tall as 20 feet; flower clusters/seed heads  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 (6-8 feet) than the non-native.  Flower cluster/seed heads are usually smaller and more open than the non-native.

The rest of this page will concern only the non-native 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 (Chicago), Zone 6, 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:

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

Flower description:

Flowering occurs in late summer. Tiny flowers 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; beige or brown in color.


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