Planted ‘bands’ of native plants may be tool against wildfires


Fountain grass is not established on Maui, but on Hawaii island, it helps to fuel wildfires. On Maui, other nonnative grasses do so to a lesser extent. — Photos courtesy of the U.S .Forest Service

A few hundred feet from the traffic of North Kihei Road, native dragonflies swoop and dive, snatching their food mid-flight. The endangered aeo (Hawaiian stilt) and alae keokeo (Hawaiian coot) probe the mud and vegetation for small shrimp while an aukuu (black-crowned night heron) stalks fish for dinner. The coastal strand, salt marsh and wetlands at Kealia Pond National Wildlife Refuge are thriving, thanks to the hard work of dedicated staff and volunteers who remove invasive plants, fence out feral animals and plant native species in this 700-acre refuge. But decades of protection and restoration efforts almost disappeared in a puff of smoke.

In July 2019, 25,000 acres of Central Maui burned in a series of brush fires that shut down roads and isolated communities as firefighters and helicopters worked through the night to put out the blaze. The flames burned right up to the edge of the refuge, singeing trees.

Fire poses one of the greatest threats to restoration projects, particularly in dry, arid environments like South Maui. Hawaiian ecosystems and native flora are not adapted to fires — which are mostly human caused. Invasive plants, such as fountain grass (Cenchrus setaceum), can fuel fire cycles by growing quickly and leaving behind piles of dry biomass, then germinating rapidly after a wildfire. Nonnative buffel grass and red top natal grass serve as kindling on Maui. With global warming, drought periods are predicted to become more common, fostering the conditions in which fires start and spread.

Researchers are testing strategies in Hawaii to limit the spread of wildfires in areas dominated by fire-promoting grasses. Green fire breaks — strategically planted strips of vegetation — have been effectively used in the continental U.S. as a complement to traditional firefighting methods. Water-rich and inflammable plants can help deprive wildfires of fuel, while also serving as habitat for other native species and a seed source for restoration projects.

“Green strips planted with natives can give added value to conservation areas,” explains Susan Cordell, research ecologist with the U.S. Forest Service and director of the Pacific Fire Exchange. She is exploring how this technique can be used in Hawaii with some of the native plant species used in dryland restoration. She evaluated several different species for their flammability and resistance to invasion — looking for ones that won’t allow fire-promoting grasses like fountain grass to take over. Her findings are offering restoration programs a host of options for the use of green fire-breaks.

Researchers on Hawaii island evaluate native plants for water content, inflammability and resistance to invasion by fire-promoting grasses. — Photos courtesy of the U.S .Forest Service

Aweoweo (Chenopodium oahuensis), a low-growing shrubby plant with a high-water content, stood out for its lack of flammability and resistance to invasion from fountain grass. The small glossy-leaved naio (Myoporum sandwicense) was also a contender due to its inflammability. “This isn’t a silver bullet,” cautions Cordell. “It’s just one tool in the tool-box.” Bands of native shrubs could add a protective ring around the birds and their habitat at Kealia Ponds.

Expand your knowledge about wildfires in the Hawaiian Islands by going to www.paci ficfireexchange.org/hawaii. Learn more about Kealia Ponds National Wildlife Refuge at www.fws.gov/ refuge/Kealia_Pond/.

Explore volunteer opportunities on the refuge by contacting Kealia Pond National Wildlife Refuge Visitor Services Manager Courtney Brown at courtney_brown@fws.gov.

* Lissa Strohecker is the public relations and education specialist for the Maui Invasive Species Committee. She holds a biological sciences degree. “Kia’i Moku,” “Guarding the Island,” is prepared by the Maui Invasive Species Co-mmittee to provide information on protecting Maui from invasive plants and animals that can threaten the environment, economy and quality of life.


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