Cypress trees can live for thousands of years. Some over 2,600 years old have been found in the United States. Tree ring expert David Stahle found one of them along the Black River in North Carolina. Stahle, a dendrochronologist at the University of Arkansas, cores cypress trees to learn their age and to find out what they can reveal about soil moisture during the trees' lives.
The process involves taking a pencil-thin core from the tree in a way that does not endanger it. An article about the cypress trees called Ghost Forests, written by Joel K. Bourne Jr., appeared in, I believe, the August 2023 issue of National Geographic.
The ancient trees are disappearing for several reasons. Just 120 years ago, swamps containing bald cypress trees covered about 40 million acres of forested wetlands in the southern United States. But by 1935, 90 percent of the ancient bald cypress trees in the U.S. had been cut down.
The loss of those trees has had disastrous effects in some places, such as Louisiana during Hurricane Katrina. Though Louisiana once had lush cypress forests, over the years most of them were cut down and the swamps were drained. The city of New Orleans sits on some of those old cypress swamps. Over time, the city sank many feet below sea level, Bourne wrote in the National Geographic article. As a result several parts of the city were flooded during Katrina.
Conservation groups such as the Ponchartrain Conservancy have been planting many cypress trees as a buffer against hurricanes and to provide other benefits. Other actions also have been taken to make the city safer from devastating storms.
The value of cypress trees was not always recognized. Through the Swamp Land Act of 1850, the federal government targeted swamps for destruction. The Act "gave unclaimed federal wetlands to several southern states, requiring that the proceeds from land sales be used to drain them," Bourne wrote.
The federal government apparently did not understand back then that cypress trees can withstand months of flooding, and the soil around their roots have an amazing ability to absorb storm water and carbon. Their intertwined root system lets them stand firm even in furious winds.
In spite of their resiliency, cypress trees are dying because they cannot survive rising tides that push salt water into what were once freshwater ecosystems. When trees are surrounded by water with more than two parts per thousand of salt, they start to die. Though not all cypress trees grow in areas being invaded by sea water, some cypress forests are dying along coastlines from Delaware to Texas, the National Geographic article revealed. Scientists estimate that as seas continue to rise, all the coastal forested wetlands in the U.S. could be gone by 2100.
But all is not lost. Conservation groups are planting many cypress trees. Individuals like Stahle
and organizations such as the National Geographic are doing what they can to educate people
about the trees' importance.