Common Rush
REPORT IF SEEN: This species is currently controlled by KISC, if you see it please report it.
Common Rush
Species: Juncus effusus
Family: Juncaceae
KISC is actively controlling this species. Sightings of this pest should be reported immediately. If you suspect that you have any of our targets on your property, KISC will survey and if confirmed, will remove it for free.
Description
- A high and low elevation invader of wetland and bog areas, but known to invade pasture land and well drained areas
- Clumping perennial rush with dark green leafless round stems.
- Also known as Soft Rush because of its soft stems that when opened have a spongy pith inside
- Flowers are light green to brown and emerge from the side of the stems in a droopy manner
- Plant grows from 15″ – 32″ in height
Impacts
- An environmental weed, displaces and out-competes native species
- Once established, hard to control because of rapid reproduction
- Spreads by shoes, by seeds getting trapped in boot tread or sticking to shoes
On Kauai
- First collected in 2008 along Pihea trail
- Now found along Pihea Trail and Alakai Swamp trail
- Delimiting surveys are being conducted in surrounding bogs
- On the Pono Endorsement Black List. Pono Endorsed Nurseries and Landscapers have agreed to immediately discontinue the sale of common rush.
- You can plant pono by reporting common rush to KISC at 808-821-1490 or kisc@hawaii.edu . KISC crew members can remove it from your landscaping free of charge and help identify suitable replacements.
Look-a-likes:
There are two native sedge species that look similar to Juncus effusus
Makaloa
Cyperus leavigatus
Native Hawaiian sedge that often grows in low elevation wetland. It has circular stems, but does not clump like J. effusus and has a much smaller inflorescence.
Molokai Sedge
Carex montis-eeka
Native Hawaiian sedge that grows nearby J. effusus in the Alakai. However, the Carex has stiff leaves that if cut in half would hold the shape of a “U” instead of being round.
