By Jenny Staltovich
The pet trade, plant nurseries and international shipping ports have long been blamed for spreading destructive invasive species in Florida.
But there’s another, less understood super spreader: hurricanes.
The powerful storms can transport species with high winds and flood water. They can also cause more enduring damage by wiping out native habitat, clearing the way for exotic species.
“They take hold and you have this alternative ecosystem and it’s hard to go back,” said Luke Flory, an ecologist at the University of Florida’s Institute of Food and Agricultural Sciences. “And then those invasive plants may have a different ecosystem function. They may not provide protection for the coastline for future hurricanes.”
But what if scientists could predict that spread, like a hurricane forecast track, once a storm hits?
That’s what Flory hopes could eventually come from a massive mapping project he and a team of researchers have undertaken.
“If we can identify invasions when they’re small,” he said, “we can manage them and remove them before they become large and more destructive.”
For their project, they’re looking at two of the state’s most destructive invasive plant species, Brazilian pepper and Old World climbing fern. State and federal wildlife managers spend about $45 million annually on invasive plants, with these two accounting for the lion’s share. By mapping them now, they can study how the plants respond to tropical storms and hurricanes and eventually provide forecasts.
By James Steinbauer
The secret to fewer fires may be having more people in the state who can start them.
Scientists and land managers almost universally agree that prescribed fire is the single best tool available to help mitigate wildfire risk. Landowners in the American Southeast use more prescribed fire than in any other part of the country. But across much of the American West—which has captured an outsize proportion of the public imagination around wildfire—scientists say land management agencies aren’t using fire nearly enough.
In 2017, federal and state forest managers, ranchers, and private property owners in Florida, which many fire scientists consider the prescribed fire capital of the country, burned more than 2 million acres, according to data compiled by the nonprofit Climate Central. That same year, California—which is twice the size of Florida and has six times more acres in public land—burned less than 50,000 acres. Oregon burned 48,000, Idaho 33,000, Montana 24,000, and Nevada 5,000.
Like in Florida, Native American cultures throughout the United States used fire to manage the land. But in the West, much of the land taken from Indigenous groups was redrawn as public “forest preserves.” In the absence of Native American land management, many of the places where they had previously used fire to clear the landscape became dense and overgrown. In 1910, a series of wildfires burned more than 3 million acres of forest in Montana, Idaho, and Washington. Known collectively as the Big Blowup, the blazes spooked the nascent US Forest Service into adopting a policy that demanded all fires be put out by 10 A.M. the day after they were reported. Because much of this land was publicly owned, federal land management agencies could efficiently enforce this policy of suppression.
In southeastern states, such as Florida, where most forestland is privately owned, people simply never stopped burning it. Even the US Forest Service in the Southeast dabbled with prescribed fire—the first-ever lit on federal land was in Osceola National Forest in 1943.
Florida’s position at the foot of the North America, its peninsula stretching languidly toward the tropics, results in diverse set of forest communities including about 465 species of native trees and shrubs. Add to that a wide array of introduced species and you have one of the longest lists of champion trees in the United States.
Florida has the nation’s largest recorded specimens for 94 different species. That’s out of 695 for the entire nation. A database maintained by the Florida Forest Service lists state champions for an additional 167 species. National champions are the largest specimens of their species in the state, but are not double counted as state champions.
Trees vying for the title of champion are scored by adding their circumference in inches, height in feet, and one-forth of the average crown spread in feet. The largest Florida tree of any species is a kapok tree (Ceiba pentandra) in Palm Beach County. It has a circumference of 899 inches (23.8 feet in diameter) and a height of 74 feet.
The kapok is an introduced species, so the largest specimen of a native species is a bald cypress (Taxodium distichum) in Hamilton County. It has a circumference of 557 inches (14.8 feet in diameter) and a height of 84 feet.
Champion trees don’t have to be huge. The national champion corkwood (Leitneria floridana) in Leon County is only nine inches in circumference and 17 feet tall.
Miami-Dade County has the greatest number of champions with 23 national champions and 39 Florida champions. Alachua County, home of the University of Florida, is second with six national champions and 19 Florida champions. Monroe County which includes the Florida Keys has the highest number of national champions, 24, and four additional Florida champions.
They are iconic to Florida, but palm trees offer little shade to urban heat islands and capture very small amounts of carbon, a greenhouse gas contributing to global warming.
South Florida’s palm trees are postcard promises of sighing sea breezes and sandy beaches, but the icon of the tropics may be an impractical adornment in an era of climate change.
From the regal royal palm to the sometimes shabby cabbage, the perennial symbol of the Sunshine State offers little shade to baking urban heat islands and captures minimal amounts of carbon — a greenhouse gas contributing to global warming.
As city officials look for more ways to cool concrete jungles and balance carbon emissions, the priority for new plantings is often broadleaf hardwood trees, not the idyllic palm.
Live oaks can absorb and store 92 pounds of carbon a year with a mature tree’s canopy spanning more than 100 feet. That’s compared to less than one pound of carbon for a royal palm and its compact crown of 15 to 20 fronds.
“People coming from up north or other parts of the country are expecting to see palm trees, so I don’t see them disappearing entirely from the landscape,” said Charles Marcus, a certified arborist who wrote an urban tree management plan for West Palm Beach. “But it would benefit most communities if they increased the percentage of hardwoods and I think it’s something cities will have to consider.”
Palms aren’t even an option at City of West Palm Beach community tree giveaways, and a 2018 city ordinance puts an emphasis on using more shade trees in new construction, especially parking lots where 75 percent of the required trees must now be shade trees.
“We’re not trying to seek out and replace palm trees with canopy trees, but we are looking at if we have to do a replacement, would a canopy tree fit,” said Penni Redford, resilience and climate change manager for West Palm Beach.
Three years of studies in cities including Baltimore, Richmond, Va., and Washington by the National Oceanic and Atmospheric Administration found that areas covered in concrete with few trees could be 17 degrees warmer than shaded areas.
The same study conducted in West Palm Beach this past August found a heat-index temperature of 122 degrees near downtown, compared to 92 degrees taken during the same time period near the wetlands area of Grassy Waters Preserve.
“These are samples taken in one time period and one day out of the year, but given the conditions, the difference is staggering,” said Michael Rittehouse, sustainability project coordinator for West Palm Beach.
Looking to build a new deck? You’ll probably want to use high quality 5/4 decking, likely made of southern yellow pine. Much of it comes from the Gulf coastal lowlands of Florida where slash pine (Pinus elliotii) grows in abundance. Whether from natural stands or plantations, slash pine grows straight and clear, making it ideal for this product.
On October 15, 2019, members of the Florida Society of American Foresters toured the Conifex Timber, Inc. sawmill in Cross City to see for themselves. Conifex, a British Columbia firm, purchased the Suwannee Lumber Company mill in 2018 and owns two other U.S. mills in Arkansas. Raw material and markets align to make decking the primary product for the Cross City mill although one-inch and dimensional lumber are also produced.
Here’s a basic outline of the process:
- Timber dealers deliver loads of sawtimber to the mill’s yard where they are weighed, off-loaded, and stored.
- When ready for processing, logs are debarked, analyzed for grade, and cut to optimal length.
- The log sections, or bolts, are sorted based primarily on diameter before being sawn.
- Each bolt is scanned and the saws are set to produce the highest value combination of boards possible.
- The rough lumber is sorted into bundles according to length, width, and thickness, then stacked for drying.
- Stacks of green lumber are sent through continuous-feed, sawdust-fired kilns to reduce the moisture content.
- The dried boards are planed and then bundled for shipping
The optimization algorithms are adjusted roughly weekly based on changes in lumber prices. While maximizing the value of the mill’s output in real time is crucial, the specific needs of long-term customers must also be considered. The mill’s lumber finds its way into the products of many secondary manufacturers including mobile home builders and wood treatment facilities. Nothing goes to waste. Sawdust produces energy, bark becomes mulch, and shavings provide bedding for horses.
The operation provides a lot to think about as you’re lounging on that new deck.
The Cummer Oak is a live oak (Quercus virginiana) located on the grounds of the Cummer Museum and Gardens, 829 Riverside Ave, Jacksonville, FL 32204. It is estimated to be 175 to 200 years old. It is 21 feet in circumference, 80 feet tall, and with a crown spread of 138 feet.
The Cummer family found the majestic oak on the banks of the St. Johns River when they moved to Florida from Michigan in the 1890s. Arthur and Ninah Cummer built their home around the tree in 1902. After Ninah’s death in 1958, the property and Ninah’s art collection were transferred to a foundation which opened the museum in 1961. The Cummer Oak was added to the National Register of Historic Places in 2010.
By Beth Gavrilles
The longleaf pine forests of the southeastern U.S. depend on frequent fire to maintain their structure and the diversity of plants and animals they support. New research from the University of Georgia has found that fire may be playing another, unexpected role: releasing excessive nitrogen that appears to have accumulated as a legacy of prior land use.
“It was not what we were expecting,” said senior author Nina Wurzburger, an associate professor in the Odum School of Ecology. “We first were wondering whether there was enough nitrogen fixation to balance nitrogen losses from fire, and now our hypothesis is that fire might be necessary to remove excess nitrogen from these ecosystems. We basically turned the question on its head.”
“We came to the conclusion that fire might be getting rid of excess nitrogen,” said Wurzburger. “Most of the longleaf pine that exists today has been planted, and those areas have legacy effects of agriculture or grazing or fire exclusion. Our research is suggesting that all those things, and nitrogen deposition too, have put too much nitrogen in the ecosystem. So maybe we should think about fire as a management tool to remove nitrogen that accumulated historically, and to help return these ecosystems to their natural nitrogen-poor state.”
Understanding the interacting role of fire and historical disturbances in longleaf ecosystems is important for several reasons, including carbon sequestration and the conservation of biodiversity: longleaf savannas can contain more than 40 species of plants in a square meter, and harbor a number of rare species of plants and animals, including the federally endangered red cockaded woodpecker.
By Mark Tancig
We can use science to guide the replanting so that we choose wind-resistant species and implement other best practices to prevent future damage.
In the aftermath of Hurricane Michael, with our neighbors to the west still recovering, many folks may be questioning the wisdom of having trees near their house. The value of trees to our own health (oxygen, air purification, quality of life benefits), home values, energy savings, and wildlife habitat is pretty well agreed upon.
However, many of us, or someone we know, recently experienced a tree coming down on their house, car, or other valuables. There’s nothing like a tree falling through the roof to keep you from wanting to plant another one.
Yet, we need trees. With the continued loss of forests to development and the growing body of knowledge regarding current and future environmental issues we face (think climate change and loss of species), we can’t afford to not keep planting trees. In fact, we should be planting more!
So how do we justify planting more trees in a hurricane-prone area when many of us just witnessed a lot of damage caused by the trees? Well, we can use science to guide the replanting so that we choose wind-resistant species and implement other best practices to prevent future damage as much as possible.
Fortunately, the University of Florida’s Institute of Food and Agricultural Sciences (UF/IFAS) has faculty and staff who collect and synthesize data on how trees handle hurricanes so that citizens can use that information to make better, informed decisions. They noticed trends when studying information collected following nine hurricanes, from 1992 to 2005, that ranged from top winds of 85 to 165 miles per hour.
The researchers broke the results into three different areas that affected the resilience of trees and included lessons learned regarding the health of the community’s urban forest, the individual trees themselves, and the root zone conditions surrounding trees.
Some of the results will seem straightforward.
For example, more trees fall in higher intensity storms and older, poorly structured trees with damaged roots don’t perform as well. Other data collected provided insights into which trees and environmental conditions make for a more resilient urban forest, such as the fact that trees planted in groups fare better. Much information was gathered on which tree species performed best in the face of high winds.
By Brian Kahn
TORREYA STATE PARK, FLORIDA—Religious scholars have long debated where Noah constructed his floating zoo made of “gopher wood” (Genesis 6:14) and what tree the ark’s gopher wood even came from. Some residents in the Florida Panhandle have an unlikely answer. The place in question is, well, there, and the tree in question is torreya taxifolia. Known locally as gopher wood (or, less Biblically, as stinking cedar for the astringent smell it releases when needles and stems are rolled between the fingers), local legend has it that the tree with its supple yellow wood was used to build the ark that Noah rode out 40 days of floods on, with the menagerie landing, eventually, on Mount Ararat in Turkey.
Now, thousands of years later, the tree faces a new era of ecological violence.
“If we don’t do anything, the trees will go extinct.”
Torreyas have been trapped by geography for millennia, only living in a few ravines that cut across the Apalachicola River Basin. That’s left them vulnerable to the outside disturbances that have come crashing into the Florida Panhandle and now threaten their very survival. Globalization delivered a fungus the tree had no defense against that has been slowly strangling torreyas to death for decades. Then last October, Hurricane Michael rapidly spun up into a Category 4 storm, plowing through Panama City and into the Panhandle. Its path was like a catastrophically precise ecological bomb with the strongest winds passing right over the Apalachicola Basin. The storm toppled canopy trees that either crushed the shaggy torreyas or exposed them to harsh sunlight, which can kill them. The already critically endangered tree is now on life support with just a few hundred individuals left in the wild.
Conservationists are in a race to save the trees that remain. Local volunteers and scientists from the Atlanta Botanical Garden are using a mix of mapping, genome sequencing, and conservation techniques to find trees hearty enough to survive in a world that’s become less hospitable since Biblical times. If successful, their efforts could yield a model for how to protect forests around the world from increasingly formidable threats of climate change and invasive pests.
By Janet Marinelli
Edward O. Wilson clambered partway down a slope in the Florida Panhandle, aided by a park ranger and trailed by a few dozen scientists, conservationists, and local landowners. The group had gathered in Torreya State Park, a landscape of dazzling botanical diversity along the upper Apalachicola River, as part of a whirlwind two-day meeting early this month to ponder the fate of its most storied tree. As the wind gusted through leafless branches, the lanky, white-haired Wilson, at 88 years of age still one of the most brilliant biologists of his generation, planted a seedling of the Florida torreya, North America’s most endangered conifer.
Wilson first visited the Apalachicola bluffs in 1957, as a self-described “young guy” with a new position at Harvard University, on an ant-collecting trip in Florida. “I came here,” he recounted, “the way you would go to Paris to visit a cathedral. I just had to see the torreya.” The trees had already begun their steep decline.
More than 60 years later Wilson was back. This time he declared the site “is not only a cathedral, but also a battleground at which one of the greatest events in American history will take place” — a turning point, as he sees it, in the planetary struggle to slow biodiversity loss.
Last spring, another “young guy” was at Torreya State Park on a camping trip with his lab. University of Florida forest pathologist Jason Smith “couldn’t believe how much worse the torreyas were” than when he had seen them the year before. “The population was crashing.” Smith, who has reddish brown hair and a bundle of energy, decided to assemble a team to reflect on the meaning of the species’ imminent demise, to catalog the “torreya tree of life” — all living things with which it associates in the wild — and to plan a last-ditch effort to save it.
“This is a now or never moment for the species,” he says.
While the massive wildfires and tree die-offs out West have gotten most of the press in recent years, the Eastern forests are also in crisis. An increasing number of the region’s iconic native trees are plagued by pests and pathogens introduced from abroad. This has researchers scrambling to find genes that can help impart resistance, and to breed them into the ailing trees. Because classical crossbreeding takes decades — perhaps too long for a critically endangered species like the torreya — options once unimaginable as conservation measures are now being considered, including the new group of gene-editing technologies called CRISPR that has taken the biotech world by storm.
The growing forest health crisis is forcing scientists, conservationists, and the public to answer some of conservation biology’s thorniest questions. Will we be able to use biotechnologies on the frontier of plant science to rescue imperiled species? Should we? And when so many species are at risk, does it make sense to go to extraordinary lengths to save a tree like the Florida torreya that has a tiny historical range and no commercial value?