After Long Island wildfires, pine barrens need controlled burns, ecologists say

The wildfires that erupted in eastern Suffolk County last weekend spread through more than 400 acres of woodlands before they were extinguished. But in spite of the alarming billows of smoke, the fires were not catastrophic. Quite the opposite, ecologists argue: Long Island’s pine barrens have burned too little in recent years.

If wildfires must be suppressed for public safety, ecologists say, forest managers need to set small, controlled fires to improve the health of the pine barrens and reduce the risk of a really big, fast-spreading conflagration.

"The ecosystem really needs the fire," said Polly Weigand, the Northeast fire project manager for the nonprofit Forest Stewards Guild. "If you're not going to let wildfires burn, then you need to substitute another type of disturbance — a proxy for wildfire."

Still, Long Island firefighters said it's too dangerous to allow the forests to burn uncontrolled, preferring instead planned fires that can be closely watched.

Pine barrens susceptible 

Native Americans used fire to manage woodland landscapes for thousands of years, employing periodic burns to clear away the dead organic materials that accumulate over time. They understood that fires improve biodiversity, allowing a succession of plants to grow in the newly open understory — ferns and mosses giving way to grasses and wildflowers and later to shrubs and slender saplings. Without it, a forest becomes very dense and less healthy, as crowded trees and shrubs compete for sunlight, moisture and nutrients.

Early Europeans declined to learn the technique, and for hundreds of years it was standard practice across much of the continent to immediately suppress any fires that ignited. That "culture of fire suppression," Weigand said, "has degraded the forests’ health."

Foresters now recognize the critical role of fire in many grassland and woodland ecosystems.

On Long Island, the turning point came 30 years ago, when the Sunrise Fire consumed 4,500 acres of overly dense pine barrens. Afterward, the state Department of Environmental Conservation started a program of prescribed burns to maintain forest health.

The practice is particularly important for the pine barrens, an ecosystem that has evolved to withstand and even depend on wildfire. Pitch pine cones are coated in a thick resin, which melts away under scalding temperatures, allowing seeds to be released.

The absence of fire for many years has made the pine barrens more susceptible to pests, including the deadly southern pine beetle. In the barrens’ typically sandy, nutrient-poor soil, crowded trees are less robust and produce less pitch, which is the pine’s only defense against burrowing insects.

The crowding also helps infestations spread more effectively. Female pine beetles emit pheromones that attract others, but if trees are widely spaced, some of those messages will be "diluted by the wind," Weigand said, and the beetles will "veer off course." In an overstocked forest, there’s a better chance the message is received, leading reinforcements to the target tree.

But the large number of dead standing trees killed by the southern pine beetles in the past decade hasn't increased the risk of fire, according to forestry experts. "What drives fire is the small fuels, the needles," DEC supervising forester John Wernet said at an East Hampton Town Board work session on Tuesday. "Large, dead standing trees really don’t drive the fire."

There are one-hour fuels, like pine needles and twigs, that ignite and spread flames rapidly, and 10-hour fuels such as brush that take a little longer to ignite. Dead trees are 1,000-hour fuels: "It will just smolder;  it doesn’t burn," he said.

Last weekend’s fires broke out in a rare ecosystem of dwarf pitch pines, a variety that grows no more than about 20 feet high and is found in only a few other places besides Long Island. Southern pine beetles don’t generally attack the dwarfs, as they prefer larger specimens. But when fires erupt among dwarf pines, their diminutive stature can help  fire spread. Flames can reach into low branches and climb into the crown, and then leap to surrounding trees. The Westhampton fires were extinguished before that became a significant hazard.

To the extent the pine beetle has increased fire risk, it’s an indirect effect, Kathy Schwager, an ecologist at the Brookhaven National Laboratory, told Newsday in January.

When trees die and drop their needles, the open spaces and light can encourage a profusion of growth in the understory. That growth, especially if there’s a drought, can become fodder for wildfires.

Suffolk fire: Vigorous fights to continue 

Firefighters will continue to vigorously fight accidental wildfires; even in the region's least dense areas, it's not practical to let them burn. "We wouldn’t allow that," Rudy Sunderman, the fire coordinator for Suffolk County, said in a phone interview. "It’s not safe for the community." 

But, he said, "We always support the prescribed burns. Because there’s a plan in place — when to do it, how to do it." 

Long Island’s pine barrens cover 105,000 acres — a small remnant of a forest that once extended over a quarter million acres, but still a very large landscape to manage with controlled burns. The DEC concentrates its efforts on the wildland-urban interface, where forests border residential neighborhoods — areas such as Rocky Point Pine Barrens State Forest. The agency’s staff started work there in 2022 and is still "clearing dense understory vegetation and will begin marking trees for removal soon," DEC forester Rob Cole said in a statement. "Once dense vegetation is cleared and trees removed, prescribed fire is used to maintain the open barrens."

In the David A. Sarnoff Pine Barrens State Forest in Riverhead, the DEC has already thinned more than 500 acres and has conducted prescribed burns on 50 acres, Cole said.

Suffolk County's Parks Department has been thinning in areas affected by the pine beetles, and fires have been applied in other state, and town-owned lands as well. 

These burns have to be carefully planned before torches are brought in. Crews break up a large area into a series of smaller "burn units" that can be monitored, said Tim Byrnes, a DEC forest ranger captain.

And the landscape has to be prepared to make sure "the fuel is burning in a safe and controlled manner," Weigand said. Taller shrubs are cut and "masticated" so the fire can’t use them as a "ladder" to climb into the tree canopy.

The conditions for a burn have to be just right: not too wet or it won’t work; but not too dry or windy. Crews remain close by to manage the flames. "We don't just light it and let it go," Byrnes said.

Although there’s broad agreement among foresters that these controlled fires benefit the ecosystem and improve public safety, "it's still not at the scale that we need to do it," Schwager said.

In the wake of the Westhampton fire, Schwager elaborated: "Prescribed fire is inherently risky. There are people who are concerned that the fire might escape" — which she said has occasionally happened — so outreach and education are necessary parts of a prescribed fire effort. 

The larger problem, though, Schwager said, is "forest management just isn't a priority, or it hasn't been."