Pest Alert! KISC has recently learned of this new invader! As of September 2015, we know of its distribution only along Pihea and Alakai trails in Koke‘e. Please keep your eyes peeled for any new populations so we can stop the spread fast!
- 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
- 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
- First collected in 2008 along Pihea trail
- Now found along Pihea Trail and Alakai Swamp trail
- Delimiting surveys are being conducted in surrounding bogs
There are two native sedge species that look similar to Juncus effusus.
- Cyperus leavigatus or Makaloa is a 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
- Carex montis-eeka is also a 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.