Carbon Storage in Longleaf Pine Roots

“Longleaf roots are pretty legendary,” says USDA Forest Service scientist Peter Anderson. “It’s common to hear that you can dig up a really old stump and use it as a quick, reliable kindling.” Pines contain oleoresins, a sticky liquid mix of oil and resin (or rosin). “There are companies today that buy and dig old…  More 

Long-Term Research Yields Understanding and Insights

Gaze at a painting for long enough, and you may notice details that you didn’t see right away: light, movement, and texture. This happens with research data, too. “At Coweeta, we all talk about how everything fits together,” says USDA Forest Service scientist Jennifer Knoepp. “We have been analyzing long-term watershed data for more than…  More 

30 Years of Nitrogen Fertilization in Spruce-Fir Forest

Rocks and sediments bind up almost 98 percent of all nitrogen. The remaining 2 percent is in motion, part of a global chemical cycle that includes humans, bacteria, plants, and the atmosphere. “Plants need nitrogen to grow,” says U.S. Forest Service research ecologist Steve McNulty. “However, excess nitrogen can harm plants.” Nitrogen and sulfur can…  More 

Black Locust & Drought Tolerance

By affecting plant growth, drought could potentially affect the nitrogen cycle too. “Some plants – with help from their bacterial companions – can fix atmospheric nitrogen,” says U.S. Forest Service researcher and project leader Chelcy Miniat. Atmospheric nitrogen gas, or N2, is plentiful. This form of nitrogen is inaccessible to most plants. However, legumes such…  More 

Forests, Farms, or Houses?

Molecules relentlessly cycle from one form to another. “Simple human activities, such as building homes, can affect these cycles,” says U.S. Forest Service research soil scientist Jennifer Knoepp. For example, trees growing near streams affect the way nitrogen and other nutrients move from the land to the water. “Riparian zones play a critical role in…  More 

Mount Ascutney Visitors Enjoy the View and Learn Something, Too

Over the past decade, countless visitors on southeastern Vermont’s Mount Ascutney have read the words on two interpretive panels describing ongoing research that began as a graduate student’s research project there. Through the years, the panels have faded and weathered, but now they are new again after U.S. Forest Service researchers installed updated replacements in…  More 

Scientists Find Evidence of Regime Shift in Forest Watershed Cut in the 1970s

After disturbances, healthy ecosystems are usually resilient enough to return to a pre-disturbance state. However, some disturbances are extreme enough to permanently shift an ecosystem, a phenomenon known as a regime shift. “Ecosystem regime shifts have been well documented in lakes, streams, and oceans,” says Forest Service Southern Research Station (SRS) scientist Jennifer Knoepp. “We…  More 

Disturbance Affects Relationship between the Nitrogen and Carbon Cycles

Carbon and nitrogen are always on the move. Both elements are versatile – they are constantly being converted from one form to another, and are required by all living things. “Because plants, animals, and microbes also require fixed ratios of the two elements, carbon and nitrogen’s chemical cycles are inherently linked,” says U.S. Forest Service…  More 

Chemical Clues to a Forest’s Past in Nitrogen Isotope Ratios

From the depths of the soil to the top of the atmosphere, nitrogen is everywhere. It is also indispensable to plants and animals. The vast majority of nitrogen atoms contain the same number of uncharged particles. However, a few atoms are ‘stable’ isotopes that have one extra uncharged particle. Although the extra particle adds a miniscule…  More 

Finding the Nitrogen: Modeling Forest Fertilizer Runoff

Pine forests in the southeastern United States are more productive than ever, and fertilizers can take some of the credit. But not all fertilizer goes toward plant growth. Some of it runs off into rivers and streams, where it can degrade water quality. A number of water quality models are available  to predict fertilizer runoff. A…  More