Hawai‘i Army National Guard

HILO, Hawaii – The Hawaii Army National Guard Environmental office is hunting down and eradicating the invasive species Miconia on Keaukaha Military Reservation near Hilo.

The team from environmental partnered with the Big Island Invasive Species Committee (BIISC) and University of Hawaii in the largest manpower effort to date on State Department of Defense property.
Miconia (Miconia calvescens) is considered very invasive and is on the Hawaii State Noxious Weed List. Miconia, native to South and Central America, was introduced to Hawaii as a garden plant in 1961. Miconia forms thick stands, shades out native plants and completely takes over moist and wet forests, also causing erosion.

“What it does is shade out every thing, so nothing can grow under it,”
said Angelia Kieran-Vast conservation program manager with the DOD Environmental Office. “Eventually creating a desert forest. Meaning, when you step into a regular forest you hear all kinds of sounds of life but when you go into a Miconia forest you don’t hear anything.
Like a desert, it is silent.”

The crew divided the three-acre property up in 100-meter wide tracks then traversed the dense undergrowth of the lowland wet forest looking for the Miconia plant. When a plant is found the seedlings and immature plants are pulled while the larger plants are treated in place with herbicide. The treated plants will die within a few weeks.
The sweeps started Monday Aug. 13 and continued until Thursday locating around 4600 younger, and two flowering adult plants.

Miconia can grow from seed to mature seeding tree in four years, and a mature tree can produce about three million seeds several times per year. Seeds are spread largely by birds that eat the fruit, and remain viable for ten or more years before sprouting. Introduced to Tahiti in 1937 and has since overwhelmed two-thirds of Tahiti’s forests, and is directly responsible for threatening 25 percent of their native forest species with extinction. There are large infestations of Miconia on the windward side of the Big Island, with a smaller population on the leeward side.

The number of Miconia found on KMR had a major increase in 2010 leading to a focused effort to eradicate the invasive plant. Each team member is armed with a machete, compass, and or GPS unit as they navigate through the dense wetland forest. They coordinate with radios and voice calls often not being able to see one another just five feet away. Large plants are tagged via GPS so that further tacking of that area is can be carried out in the future. The HIARNG Environmental office plans to perform sweeps of their property on a quarterly basis.