Considered very invasive and is on the Hawaii State Noxious Weed List. The Division of Forestry and Wildlife of the Hawaii Department of Land and Natural Resources has designated this species as one of Hawaii’s Most Invasive Horticultural Plants.
- A grass that can grow up to 20 ft. tall
- Looks a little like sugarcane, but leaves are shorter and alternately arranged along stem
- Flowers are long, dense, and plume like
- Native to the Mediterranean region, introduced to Hawaii as an ornamental
- Grows well along rivers, streams, and ditch channels, where masses of plant material choke drainages and cause flooding
- Crowds out native vegetation
- Thick growth reduces habitat for wildlife
- Fire hazard when dry
- Spreads easily by root and stem fragments floating downstream and taking root
- Also spreads in dry areas when dirt containing root pieces are moved (e.g. in topsoil or on heavy equipment such as bulldozers)
- KISC controls small populations in Kekaha, Kalaheo, Lawai, Omao, Lihue, Hanamaulu, Wailua, Kapaa, Anahola, and Kilauea. Please report any sightings!
- Saccharum officinarum, commonly known as Sugarcane, shares a similar looking plume as Giant Reed, however its growth pattern, habitat, and leaf arrangements are very different.
- Bamboo. There are some dwarf Bamboo species that have similar looking leaves to Giant Reed, however it can clearly be distinguished by its internodes along the stem.