Sign In or Create an Account.

By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy

Climate

How Invasive Plants Fueled an Inferno in Maui

“When the land gets abandoned, the grasses are the first invaders. All you need is a little drought to have a flammable landscape.”

A Hawaii landscape.
Heatmap Illustration/Getty Images

Researchers and scientists have been tracking and anticipating more frequent and larger wildfires across Hawaii for years. While the speed and scale of the wildfire that devastated Lahaina and killed at least 36 people this week was a surprise, the fact that the state, Maui, and especially the western part of the island was susceptible to fires was not.

In 2019, fire burned some 25,000 acres on the island. A government report on the 2019 fires concluded that “Wild/brush/forest fires present a growing threat to Maui County citizen safety and property. Island communities are particularly vulnerable because populations tend to be clustered and dependent on single highways, often located on the island edge,” almost directly anticipating the disaster in Lahaina.

Research by Clay Trauernicht, a fire specialist at the University of Hawaii, and others has shown that the scale and frequency of wildfires have been increasing across in Hawaii from the early 1900s to the 2010s. The researchers also identified a major culprit: non-native plants.

“Wildfires were most frequent in developed areas, but most areas burned occurred in dry non-native grasslands and shrublands that currently compose 24 percent of Hawaii’s total land cover,” the researchers wrote. “These grass-dominated landscapes allow wildfires to propagate rapidly.”

Get one great climate story in your inbox every day:

* indicates required
  • The non-native grasses were brought to Hawaii by cattle ranchers in the 19th century, University of California Santa Barbara ecologist Carla D’Antonio told me. “They were selected because they were drought tolerant.”

    They are also invasive. The abandoned sugar and pineapple farms across the state are quickly taken over by non-native grasses. “When the land gets abandoned, the grasses are the first invaders. All you need is a little drought to have a flammable landscape.” Maui is currently in a drought.

    The grasses are an especially potent fuel, D'Antonio explained, because they grow quickly when it rains and then stick around, deeply rooted into the soil, as dry, dead organic matter, becoming a “standing layer of very ignitable fuel.”

    Then after a fire, these non-native plants tend to do better than native ones, thus increasing future fire risk. Fire “has generally been shown to decrease the abundance of native woody plants because nonnative, invasive, fire-adapted plants out-compete natives for resources in the post-fire environment and tend to dominate post-fire communities,” according to a United States Forest Service review.

    These grass fires can also grow and move quickly, endangering residents and firefighters. “They see fire at a distance and the next thing they knew the building is on fire,” D’Antonio said.

    The 2021 County of Maui report recommended “reduction of alien plant life that serves as fuel,” in order to prevent future wildfires, noting that “grasses serve as tinder and rapidly invade roadside shoulders.” Fire authorities should “implement an aggressive plan to replace these hazardous fuel sources with native plants to reduce combustible fuel while increasing water retention,” the report said.

    If grasses provide the fuel for fire in Hawaii, then strong winds can help turn them into devastating wildfires, both by spreading fire and by sucking moisture into the storm and away from land.

    “People really need to think about how they live in a flammable environment,” D’Antonio said. “They’re living with a legacy that’s going to be impossible to reverse.”

    Read more about the Maui fires:

    Your Biggest Questions About the Deadly Maui Fires, Answered

    Green

    You’re out of free articles.

    Subscribe today to experience Heatmap’s expert analysis 
of climate change, clean energy, and sustainability.
    To continue reading
    Create a free account or sign in to unlock more free articles.
    or
    Please enter an email address
    By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy
    Climate Tech

    Climate Tech Bets on Space

    In space, no one can oppose your data center.

    Solar panels in space.
    Heatmap Illustration/Getty Images, Wikimedia Commons

    An investment boom is exploding in outer space. Investors have thrown their backing behind space-based solar power, orbital data centers, and even extraterrestrial power grids. SpaceX is pursuing an IPO — potentially the largest the world has ever seen — in part to fund its own off-Earth data center ambitions. The Space Foundation reported that the global space economy reached $613 billion in 2024, combining commercial revenue and government funding, while PricewaterhouseCoopers estimates the sector could grow to reach $2 trillion by 2040, largely driven by private sector innovation and support.

    Different though they may be, these technologies all leverage the vast unknown outside our atmosphere to monitor, manage, and optimize terrestrial energy and climate systems.

    Keep reading...Show less
    Blue
    AM Briefing

    Nuclear Option

    On Chinese nuclear exports, Canadian LNG, and Otovos U.S. push

    Plutonium storage.
    Heatmap Illustration/Getty Images

    Current conditions: The French government has recorded at least seven deaths linked to the record early heatwave roasting Western Europe • New York City’s springtime temperature swing is surging upward to about 85 degrees Fahrenheit before dropping back into the 60s later this week • Temperatures in Berbera, the prized Red Sea port city in the de facto independent state of Somaliland, are revving up to 100 degrees today.


    THE TOP FIVE

    1. Trump wants to give weapons-grade plutonium to nuclear startups to use as fuel

    The Trump administration is considering handing over leftover weapons-grade plutonium that was set to be buried to companies that aim to use the highly radioactive material as reactor fuel. On Tuesday, the Department of Energy selected five finalists to submit plans to safely transfer the plutonium from a government stockpile. The companies include fuel maker Standard Nuclear, waste reprocessor Exodys Energy, fusion company Shine Technologies, and reactor developers Flibe Energy and Oklo. The move is sure to draw criticism from non-proliferation experts who worry that, unlike the low-enriched uranium used as fuel in conventional reactors, plutonium increases the threat of a rogue actor obtaining material for a bomb. “Countries have tried this before, and they concluded that, as nice as it would be to use that plutonium as fuel, it’s really just a liability and we need to dispose of it permanently,” Scott Roecker, a vice president at the Nuclear Threat Initiative, told The New York Times. In an emailed statement to me, Shine Technologies CEO Greg Piefer said the access to fuel solves “one of the hardest problems in the advanced reactor industry right now.”

    Keep reading...Show less
    Yellow
    Politics

    How New York Is Weakening Its Climate Law

    The state is the first to backtrack on binding emissions legislation.

    Kathy Hochul.
    Heatmap Illustration/Getty Images

    A wave of climate action swept the country’s statehouses in the early 2020s, with nearly two dozen states setting targets to slash their emissions. New York was ahead of the pack and among the most ambitious, passing the Climate Leadership and Community Protection Act, or CLCPA, in the summer of 2019 to achieve net zero emissions by 2050.

    Now, however, the Empire State will distinguish itself as the first of the bunch to walk back its landmark climate law in the wake of Trump’s re-election.

    Keep reading...Show less
    Blue