OREGON STATE UNIVERSITY

Managing a Monstrous Menace

In ancient Greece, there was once a beautiful maiden who aroused the jealousy of a goddess. In anger, the goddess transformed the girl into the monster Medusa, with hair made of snakes and a look that could turn a person to stone.

Today, Medusa’s namesake, the medusahead weed, spreads across the eastern Oregon plains, destroying native perennial grasses. Seema Mangla, a post-doctoral researcher in the Forest Ecosystems and Society Department, has spent several years studying the species in Burns, Oregon, observing the power of the weed’s inva­sive spread. Much as the original Medusa plagued the people of Greece, so too does the appearance of medusahead herald trouble for Oregon.

How did Mangla end up at the College of Forestry researching this monstrous invasive species? Before arriving at Oregon State, Mangla attended the University of Delhi and worked as a research assistant at the Ministry of Environment and Forestry in India. While there she met Steve Radosevich (Emeritus Professor of Forest Science) at a conference and they discussed her research interests. Mangla eventually came to the College of Forestry to pursue her PhD, with Radosevich serving as her co-advisor, along with Roger Sheley, a weed scientist with the USDA Agricultural Research Service (ARS) at the Eastern Oregon Agricultural Research Center.

After a trip to Burns and a discussion regarding invasive species, Mangla had found her focus: medusahead. “I wanted to do research and have an impact on local ecology,” Mangla says. “The biggest threat to the rangelands in eastern Oregon is medusahead.” This little-known species—especially compared with the familiar cheatgrass—“is spreading at an alarming rate in Oregon, at roughly 12-20% per year.”

The plant, covered in spiny seeds called awns, was initially used as a grazing species for cattle during the spring season. As the plant ages, however, the awns injure the animals’ mouths and they stop eating it. This allows the invasive species to spread, leading to the death of native grasses. “Therefore, it can make lands almost worthless as a forage crop, which can hugely impact these grazing lands,” Mangla says.

Mangla’s research concluded that the climate of Oregon is ideal for the rapid spread of this invasive species. Furthermore, with its high silica content and density, which make it highly flammable, medusahead also increases the possibility of wildfire, especially as the plant adapts to new soil types and advances farther west, impacting more and more lands and livelihoods in central and western Oregon. In the mythological tale, a young man named Perseus was sent to slay the deadly Medusa. Today, the battle against this new Medusa is underway, led by scientists on field sites and in research labs.

As for Mangla, her future plans include a post-doctoral appointment at the University of California, Berkeley, where she is continuing research in the Department of Environmental Science, Policy and Management (http://nature.berkeley.edu/sudinglab/index.html).

Story by Danielle White, senior, WST