StarBulletin.com

Groups aim to eradicate weed


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POSTED: Tuesday, October 21, 2008

Experts have teamed up to prevent the spread of a noxious weed on Oahu.

               

     

 

 

How to help

        » Hikers can help prevent the spread of the noxious weed cane tibouchina by brushing off their footwear and cleaning their backpacks and jackets before and after hikes.

       

» Experts recommend that people not attempt to remove the weed themselves, as they could exacerbate the problem by causing plant fragments to multiply.

       

» Anyone who observes cane tibouchina is encouraged to take a photo of the plant and provide detailed information on the location to the Oahu Invasive Species Committee at 286-4616 or .(JavaScript must be enabled to view this email address).

       

» For more information, go to www.hawaii.gov/dlnr/dofaw.

       

       

The Department of Land and Natural Resources is working with the Army Natural Resources Program and the Oahu Invasive Species Committee to prevent the spread of cane tibouchina, a potentially invasive weed that was recently discovered high in the Koolau mountains.

In August, staff members from the Army Natural Resources Program discovered an individual plant in the Poamoho region and removed it. It was the first time crew members observed the shrub near the ridge summit, home to more than 80 rare and endangered native species.

Crew members conducted a survey via helicopter to check whether more shrubs were on the summit, but none was observed.

Another individual plant was found in Halawa Valley by the Oahu Invasive Species Committee in April 2006.

“;We want to take care of it before it becomes invasive. Right now it's incipient,”; said Candace Russo, environmental outreach specialist with the Oahu Army Natural Resources Program.

Experts are concerned about the weed because it can spread rapidly and pose a threat to species such as the haiwale plant and several types of endangered lobelias, Russo said. The spread of the plant could also affect the population of kahuli, native tree snails that live in the Koolaus.

The plant can out-compete and penetrate thick native plants like the uluhe and also has the potential to “;choke out”; stream corridors that are home to native damselflies, Russo added.

The plant produces hundreds of small seeds that can ride the wind or cling to animals and hikers.

“;They are probably the worst seeds in Hawaii,”; said Laura Nelson, Big Island natural resources manager for the Nature Conservancy. “;In the moist environment, they just go nuts.”;

The plant can also reproduce from pieces of itself.

“;Just pieces of the stem or pieces of the root can grow a new plant,”; Russo said.

If the plant is improperly pulled out from the ground, pieces of it left in the ground can form new plants, she added.

The weed, which thrives in moist conditions, has hairy leaves, fuzzy square-shaped stems and purplish-pink flowers with four petals. It can grow up to 13 feet tall.

It resembles another invasive plant called pinkfringe, which is prevalent in certain parts of Oahu. The cane tibouchina, however, grows upright, while the pinkfringe, which has pink petals, tends to fall over, forming large brambles.

While rare on Oahu, the weed is widespread on Maui and the Big Island.