The Great Plains face a surprising threat: Too many trees
Trees are usually seen as climate heroes. But across the Plains states, "woody encroachment" is crowding out the prairie.
In the heart of Nebraska's Sandhills, a 19,500 square-mile stretch of grassy dunes, something alarming is happening. Rancher Shelly Kelly, who has spent her life on the prairies, has noticed an unsettling trend: trees are encroaching upon the grasslands. These are not just standard windbreaks meant to protect cattle, but rather a proliferation of eastern red cedars, known as woody encroachment.
This phenomenon, also referred to as the "green glacier," is causing significant concern among ecologists and ranchers alike. Kelly explains that the loss of biodiversity and resilience is a major worry, with $4 billion in range production potentially lost across the 10 Great Plains states. The looming threat of this encroachment extends to the water supply, as trees demand more resources and disrupt the delicate balance of the prairie ecosystem.
The Sandhills, known for their unique mix of fire, grazing, and other elements that maintain the diversity of grasses, are now facing a new challenge. Fire, originally a natural part of the prairie landscape, has been suppressed, allowing trees to take root and spread. Overgrazing by cattle and bison has also contributed to this issue, as these animals do not eat woody plants.
The Flint Hills of Kansas and Osage Hills of Oklahoma, which house two-thirds of the nation's remaining tallgrass prairie, have long relied on prescribed burns to maintain the prairie's health. However, regions that lack this cultural practice are struggling to adapt. Kelly emphasizes that while trees can be beneficial in some contexts, they are not desirable on a prairie, especially invasive species.
A cultural shift is needed to address this growing problem, particularly within the broader conservation community. The prevailing wisdom has been to promote tree planting as a virtuous act, but in reality, grasslands can be a more secure carbon sink than forests. The cycle of fire on the landscape plays a crucial role in maintaining the health of prairies, and the increasing threat of wildfires only adds to the complexity of the situation.
Written by urgent.news from Grist's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
