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Salt Cedar (Diorhabda elongata), a mealybug (Trabu- tina mannipara), and a weevil (Coniatus tamarisci), Salt cedar or tamarisk (Tamarix spp.) are and but so far, only the beetle has been approved native to Eurasia that grow five to 20 feet for use and released in nine states. Sawing and im- tall, frequently at the edge of streams and springs. mediately applying “eco-friendly” herbicide such Eight species were planted in the Southwest U.S. as Garlon to the stump is effective. Burning and during the 1800s as windbreaks, for shade, and as manipulation of water levels to mimic natural erosion control. flow regimes can favor native species. Bulldozing and plowing up roots has also been used. Aerially Problems: Salt cedar had infested 3.6 million acres spraying herbicides in areas with little or no native across 17 western states by 2003, including many vegetation can reduce salt cedar by 90%. Once it important riparian habitats for . Although a is removed, it may be necessary to actively replant few bird species can survive in salt cedar (e.g., the native vegetation. “Southwestern” Willow Flycatcher), it supports fewer insects, less mistletoe, and fewer bird species Actions: than native willow and cottonwood riparian wood- • Reduce salt cedar over large areas using biocon- lands. Southwestern populations of the Yellow- trol methods. In riparian woodlands, replace it billed Cuckoo, Bell’s Vireo, and Summer Tanager with native willows and cottonwoods. are among the birds that are nearly excluded. Salt cedar consumes large quantities of water compared to native vegetation, costing irrigators and hy- Miconia dropower producers $54-164 million annually in Miconia () is a native to Central and South America which may grow up to 50 feet tall. It has been introduced to many Pacific islands as an ornamental tree, including to the Ha- waiian Islands in the 1960s.

Problems: Miconia’s shady foliage inhibits regen- eration of native Hawaiian trees, depended on by native honeycreepers. Its shallow root system does not hold soil as well as those of displaced native forest trees, resulting in soil erosion that can dam- age nearby coral reefs. Miconia produces large

PHOTO: STEVE HILDEBRAND / FWS amounts of fruit, which is then dispersed by non- Salt cedar has infested 3.6 million acres and exudes salt, which helps inhibit the growth of native nearby. native birds. By the late 1980s, miconia dominated 60% of Tahiti causing landslides and endangering lost water. It also increases the frequency of fire in native plants and animals. southwestern riparian woodlands. Its exude salt, which accumulates in the soil beneath trees Solutions: Controlling miconia in Hawaii is im- and inhibits the growth of native plants nearby. portant to prevent damage similar to that which occurred in Tahiti. Trees can be cut and their Solutions: Once salt cedar is well established, it is stumps treated with herbicides to prevent re- very difficult and expensive to eradicate. Monitor- sprouting. Seedlings and small saplings can be ing, prevention, early detection, and local eradi- uprooted by hand. Repeated treatments may be cation are the most effective means of control. required to remove new seedlings that germinate Biocontrol agents include the salt cedar leaf beetle following the removal of adult trees. Government

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where it now forms dense stands. In 2000, it oc- cupied 13% of Midway’s 1,200-acre Sand Is- land and 39% of the 334-acre Eastern Island.

Problems: Crownbeard displaces native vegeta- tion (bunchgrass) on Midway. The Laysan and Black-footed Albatrosses, whose global popula- tion stronghold is on Midway, are unable to nest in dense stands of crownbeard. This rapidly grow- ing can also enclose existing nests, trapping albatross chicks that eventually die of starvation. Crownbeard also supports invasive ants that may harm ground-nesting birds.

Solutions: FWS started a control program on Midway in the late 1990s that includes hand- pulling and mowing to prevent crownbeard from flowering, removing stems and roots, treating with

PHOTO: ©ISTOCKPHOTO.COM herbicide, monitoring, and replanting areas with Invasive miconia shades out native trees in Oahu’s Koolau range where the “Oahu” Elepaio can still be found. native bunchgrasses and sedges.

agencies, private organizations, and volunteers Actions: have helped eradicate miconia on Oahu and Kauai, • Complete removal of crownbeard and continue and are working to eradicate it from Maui and the habitat restoration efforts on Midway. Monitor Big Island. Monitoring cleared areas for seedlings for potential return of crownbeard. is important so they can be quickly removed be- • Expand crownbeard control to Kure Atoll and fore they can re-establish. Miconia sightings can be elsewhere in the Northwest Hawaiian Islands. reported to the Hawaii Department of Land and Natural Resources. Research into potential bio- control agents (fungal pathogens and insects) for miconia is ongoing.

Actions: • Continue miconia control efforts to stamp out new infestations, and complete miconia eradica- tion from remaining Hawaiian Islands where it occurs.

Golden Crownbeard

Golden crownbeard (Verbisina encelioides) typi- cally grows one to five feet in height and is native to the western U.S. It was introduced to Hawaii prior to 1871, where it dominates some coastal PHOTO: MICHAEL LUSK areas. It likely arrived as seed in soil brought Invasive golden crownbeard can prevent Laysan Albatrosses by the military to Midway and Kure Atolls, from gaining access to their nests, and starving their chicks.

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