Invasive species along Maui roadsides to be catalogued

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Lissa Fox is public relations and education specialist for the Maui Invasive Species Committee, and she can be reached at 573-6472. An Idaho native, she holds a biological sciences degree from Montana State University. Kia'i Moku, Guarding the Island, is prepared by the Maui Invasive Species Committee to provide information on protecting the island from invasive plants and animals that can threaten the island's environment, economy and quality of life.

Chinese privet, English ivy, Spanish lavender, Mickey Mouse plant, and poison devil's pepper: Maui's roads are about to be scrutinized for exotic plants whether they sound benign or evil. They come from distant places, and all have something in common. They are on a list of more than 100 plants that Forest and Kim Starr will be on the lookout for as they scour the island over the next eight months.

This duo of self-taught botanists with the U.S. Geological Survey will attempt to survey every public road on Maui, recording each sighting of selected plants from a target list. This painstakingly slow task will require acute attention to detail, inevitably slowing a vehicle or two as the duo drives over 1,200 miles of road. Some of the plants on this list are common on Maui, like the ubiquitous fireweed, but the Starrs also seek invasive plants not yet known on Maui, such as long-thorn kiawe.

Why drive every public road on Maui rather than delve deep into the rain forest looking for weeds? Roadsides are easily accessible, and a roadside survey will allow the Starrs to monitor areas highly exposed to human impact. Roadsides are locations where many alien plants are introduced, and yet natural area managers rarely survey these areas. The Starrs will embark on a journey to see what we've left behind as we drive to work, school and, of course, the beach.

This is the second round of roadside surveys the Starrs will complete on Maui. The first, in 2000, was experimental in nature. At that time, they attempted to determine a methodology for mapping species on an islandwide scale and to provide information on the distribution of many invasive plants on Maui.

The plants included in the 2000 survey were chosen because they had been documented as being invasive elsewhere in the world. Some plants were widespread, some not, and any plant not recognized by the roving experts was collected and identified. As a result, the Starrs identified 29 plants notpreviously known to be on Maui, 11 of which were not known to be in Hawaii. They were able to locate an impressive 94 percent of the targeted plants, of which 44 percent were widespread. Eight highly invasive plants found on the roadside surveys since have been eradicated, meaning none of these plants remains on Maui.

The 2009 target plant list includes many plants mapped in 2000 plus an additional 53 species, included because of their presence on other islands. Potential invasiveness was determined using the Hawaii Pacific Weed Risk Assessment and by reviewing literature about these plants' invasive tendencies in other parts of the world. Members of the conservation, agricultural and horticultural industries also were consulted in developing the final target list.

After the surveys are complete, the Starrs will create maps showing the current distribution for the 101 plants targeted on the survey. The maps will be readily available on the Internet at www.hear.org/starr. These maps are an important tool for early detection. Detecting and removing invasive species before they become established costs substantially less than tackling a well-entrenched species. Plants identified in limited distribution may be added to the Maui Invasive Species Committee's target list for eradication on Maui before they spread and become uncontrollable.

So as Forest and Kim drive slowly along the roadsides of Maui over the next eight months, slow down and wave - they'll be easy to spot with their flashing yellow light and "Slow moving vehicle" sign. Every extra minute they spend behind the wheel will be helping protect the island from a new plant and keeping Maui the paradise we know. You could say they epitomize the bumper sticker slogan "Slow down, this ain't the Mainland" both in terms of the speed they drive and the Mainland "weeds" they will be looking for.