Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. Earth Science News .




FLORA AND FAUNA
Ailanthus tree's status as invasive species offers lesson in human interaction
by Staff Writers
University Park PA (SPX) Jun 27, 2013


This Alianthus altissima tree is on the north side of Old Main on the Penn State University Park campus. Credit: Patrick Mansell, Penn State.

An exotic tree species that changed from prized possession to forest management nightmare serves as a lesson in the unpredictability of non-native species mixing with human interactions, according to researchers.

"There are other invasive tree species in Pennsylvania, but the Ailanthus, by far, has been here longer and does more damage than any other invasive tree," said Matthew Kasson, who received his doctorate in plant pathology and environmental microbiology from Penn State. "It's the number one cause of native regeneration failure in clearcuts in Pennsylvania."

Kasson, who is a post-doctoral researcher in plant pathology, physiology and weed science at Virginia Tech, said that William Hamilton, a pioneer botanist who corresponded with William Bartram and Thomas Jefferson, imported the first Ailanthus altissima - Tree-of-Heaven - a tree native to China, from England sometime between 1784 and 1785 and cultivated the tree on his estate, the Woodlands, in Philadelphia. The deciduous tree, which grows rapidly, often to a height of 50 feet, has become one of the biggest forest management problems, especially since the 1980s, according to the researchers.

Kasson and colleagues report in a recent issue of the Northeastern Naturalist that Ailanthus can invade quickly in areas where large, continuous stands of trees are cut down - clearcuts - and displace slower-growing native plants.

The spread of Ailanthus in Pennsylvania occurred in spurts that seem to be connected with stages of human development, particularly during cross-state transportation projects, Kasson said.

While the tree was initially isolated to the properties of a few botanists and wealthy plant collectors, commercialization of Ailanthus after 1820 coupled with railroad construction projects that connected the eastern and western parts of the state in the mid-1800s intensified its spread, according to Kasson, who worked with Matthew Davis, lab assistant and Donald Davis, professor of plant pathology, both of Penn State.

In the 1980s, widespread gypsy moth infestation in Pennsylvania led to the death or near death of large stands of oak trees in the state forests, especially in south-central Pennsylvania. Crews that cut down the trees built roads to reach the sites, which became avenues for the spread of Ailanthus. From 1989 to 2004 the number of Ailanthus trees on inventory plots increased from 76 million to 135 million.

"In parts of the state forests there were no roads in areas associated with the gypsy moth devastation," said Kasson. "During these timber salvage operations, crews are building roads and moving a lot of soil and seed."

The researchers found one or two older female Ailanthus trees near areas where foresters removed trees following the gypsy moth infestation, but also discovered that most of the Ailanthus trees started to grow shortly after the clearing operation.

The older seed-producing trees were often found upwind from the sites of the recent Ailanthus growth. Kasson said this indicates that following the clearcut Ailanthus grew faster than competing species and quickly dominated these forests.

Kasson said recent mining and drilling operations in Pennsylvania forests may also cause the species to expand.

"New roads are being constructed into these active drilling sites," said Kasson. "These drilling operations could lead to future spread."

Previous research may have also underestimated how long Ailanthus can live, according to Kasson. While prior studies estimated that Ailanthus's lifespan was between 50 to 75 years, the tree routinely lives longer than 100 years.

The researchers conducted tree-ring studies of Ailanthus in all the counties where the tree grows in Pennsylvania, as well as several surrounding states. The researchers used these studies, along with historic surveys and reports on plant species in the state, to determine age and growth patterns.

Ailanthus, which is also called Chinese sumac or stinking sumac, grows in 60 of Pennsylvania's 67 counties, according to the researchers - nine more counties than reported in previous studies.

The research also suggests that the incidence of Ailanthus in Pennsylvania's northern-tier counties, where the tree has been historically absent, will likely increase like previous Ailanthus expansions in southern parts of the state.

.


Related Links
Penn State
Darwin Today At TerraDaily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





FLORA AND FAUNA
The Anthropocene: Humankind as a Turning Point for Earth
Moffett Field CA (SPX) Jun 25, 2013
The Anthropocene is the name of a proposed new geological time period (probably an epoch) that may soon enter the official Geologic Time Scale. The Anthropocene is defined by the human influence on Earth, where we have become a geological force shaping the global landscape and evolution of our planet. According to this theory, the present epoch - still known as the Holocene, which started ... read more


FLORA AND FAUNA
India chopper crash kills 20 as flood rescue forges on

India rescue chopper crash death toll rises to 20

WIN-T Increment 1 Enables National Guard to Restore Vital Network Communications Following a Disaster

Australia costs from natural disasters to soar: study

FLORA AND FAUNA
Laser guided codes advance single pixel terahertz imaging

New laser shows what substances are made of; could be new eyes for military

Google making videogame console and smart watch: report

Ames Laboratory scientists solve riddle of strangely behaving magnetic material

FLORA AND FAUNA
Sea level along Maryland's shorelines could rise 2 feet by 2050

Migrating animals add new depth to how the ocean "breathes"

El Nino, La Nina unlikely to make an appearance in 2013: WMO

Gulf of Mexico could see record 'dead zone': US

FLORA AND FAUNA
Is Arctic Permafrost the "Sleeping Giant" of Climate Change?

The rhythm of the Arctic summer

Global cooling as significant as global warming

Warm ocean drives most Antarctic ice shelf loss

FLORA AND FAUNA
Comparing genomes of wild and domestic tomato

Dutch government introduces nitrogen-reduction bill for nature areas

Rotation-resistant rootworms owe their success to gut microbes

Pesticides tainting traditional China herbs: Greenpeace

FLORA AND FAUNA
New Jersey may have been hit by a tsunami in mid-June

Calgary woman's drowning brings flood toll to four

Mexico storm upgraded to hurricane: forecasters

India flood rescue ops intensify, up to 1,000 feared dead

FLORA AND FAUNA
Mali coup leader says sorry: military source

New Sudan armed forces chief after rebel attacks

Uganda president's son denies plan to succeed father

Africa juggles East and West, as Obama comes to visit

FLORA AND FAUNA
China to fund search for origins of early humans

The evolution of throwing

Australia, Indonesia to face off over people smuggling

Outside View: Cosby's inciteful insights on Muslims




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement