How Tree Diversity Affects Invasive Forest Pests

“Invasive insects and diseases pose both ecological and economic threats to our forest ecosystems,” says Qinfeng Guo, USDA Forest Service research ecologist. Guo is the lead author of a broad-scale study of U.S. forest data that examines the relationship between the number of native tree species and the number of nonnative forest pests. Across their…  More 

Study Supports Single Introduction of Laurel Wilt Pathogen in the U.S.

Laurel wilt has devastated plants in the Lauraceae family – redbay, sassafras, pondberry, avocado, and others – since it was first detected in the southeastern U.S. around 2002. The disease is caused by the pathogen Raffaelea lauricola and carried by the redbay ambrosia beetle – and by humans moving infested wood. There is no widespread,…  More 

Hemlock Seedlings Released from Shade

Eastern hemlock typically grows in shady environments, but its world is now infested by hemlock woolly adelgids (HWA). The miniscule sap-sucking insects can kill mature trees in less than five years. “Eastern hemlock is a shade-tolerant species,” says USDA Forest Service research entomologist Bud Mayfield. “But extra sunlight may help it survive HWA infestation.” Extra…  More 

A Hemlock in the Town Square

This summer, I joined USDA Forest Service scientist Andy Whittier for a day of field work as a part of my internship with SRS Public Affairs and Science Communications. We traveled to Green Mountain, NC to check up on an experiment led by research entomologist Bud Mayfield on hemlock trees. Throughout the eastern U.S., the invasive…  More 

Why Native Plants Are Best

This article was written to celebrate Native Plant Month in Arkansas. It was originally published in Our Ozarks. In 1733, Peter Collinson, a botanist and cloth merchant, walked with great excitement to the ship docks in London. He picked up two boxes of seeds from an American farmer named John Bartram. With these exotic seeds,…  More 

How Cold Is Too Cold for Redbay Ambrosia Beetles?

Nonnative redbay ambrosia beetles and the fungus they carry have killed hundreds of millions of trees in the Southeast since first detected in 2002. Currently, only cold temperatures limit the beetles’ establishment and spread in the eastern United States. A study led by Mississippi State University involving U.S. Forest Service researchers determined the coldest temperatures…  More 

Do Roads Drive Forest Plant Invasions?

Roads provide a means for moving people and products, but they can also allow hitchhiking organisms to spread. Some exotic invasive plants thrive on the disturbance created by road construction that displaces native plants. However, a new study led by Kurt Riitters, U.S. Forest Service research ecologist with the SRS Eastern Forest Environmental Threat Assessment Center, found…  More 

Invasive Earthworms in the Food Web

Imagine walking through a forest, with leaves crunching beneath your feet. Underneath those crunchy leaves is a complex ecological realm. “Soil is teeming with life,” says U.S. Forest Service research ecologist Mac Callaham. “Most people don’t think about it because they don’t see the soil fauna.” Soil fauna includes centipedes, millipedes, springtails, nematodes, insect larvae,…  More 

The Thorny Economics of Preventing Exotic Species Introductions

What if we lose tree species we know, love, and need? It has happened before. “Look at what happened to the American chestnut,” says U.S. Forest Service research forester Thomas Holmes. “Look at what’s happening right now to hemlock, redbay, and ash trees.” All three species, as well as many more, are threatened by non-native…  More 

One is the Deadliest Number

When the redbay ambrosia beetle, native to Asia, was first detected in coastal Georgia in 2002, it didn’t set off any alarm bells. “Ambrosia beetles rarely damage healthy trees, so this find was initially considered unimportant. But the subsequent epidemic of laurel wilt in the Southeast has caused a re-examination of the significance of these…  More