Using remote sensing to track invasive trees

May 21, 2010

A team of Agricultural Research Service (ARS) scientists has refined remote sensing tools for identifying invasive Ashe juniper shrubs and trees in central Texas and nearby regions. These findings can help rangeland managers determine the extent and severity of Ashe juniper infestations and boost mitigation efforts.

Over the past century, the expansion of Ashe juniper has reduced the production and diversity of other rangeland plant species. Because Ashe juniper has little nutritional value for , the vegetative shift has also reduced forage options for livestock and wildlife.

ARS agricultural engineer Chenghai Yang and rangeland scientist James Everitt evaluated remotely sensed data to pinpoint the most accurate "signal" for identifying Ashe juniper stands, which often grow within an assortment of other woodland plants. Yang and Everitt work at the ARS Kika de la Garza Subtropical Agricultural Research Center in Weslaco, Texas.

Remotely sensed data were collected from two Texas sites that were populated with Ashe juniper and other associated plant communities. The data spanned 98 spectral bands--which are bands of light that are characterized by different wavelengths--that ranged from 475 to 845 nanometers.

Then the team used a called minimum noise fraction (MNF) transformation to reduce interference. In comparison with the original imagery, MNF imagery takes less time to process and less data space to store, especially when large amounts of remotely sensed data are being analyzed.

MNF transformation consolidated the spectral data into 50 distinct bands. Further analysis indicated that the first 10 bands from this group were the best for identifying Ashe juniper stands. Using these bands, the scientists were able to sufficiently distinguish Ashe juniper from other mixed woody species, other mixed herbaceous species bare and .

Explore further: Fears for pink iguanas as Galapagos volcano erupts

More information: Results from this work were published in the International Journal of Remote Sensing.

Related Stories

Spread of Western Juniper Seeds Studied

Nov 05, 2009

(PhysOrg.com) -- Aromatic, evergreen foliage and plump, dusty-blue to nearly purple berries make western juniper appealing, whether it's a small shrub or a lofty tree. The trouble is, during the past 100 years ...

In Brief: WiMax demand expected to surge

Jun 29, 2006

WiMax, or worldwide interoperability for microwave access, will become increasingly popular especially when it becomes more mobile, a research group said.

Why juniper trees can live on less water

Feb 27, 2008

An ability to avoid the plant equivalent of vapor lock and a favorable evolutionary history may explain the unusual drought resistance of junipers, some varieties of which are now spreading rapidly in water-starved ...

Recommended for you

Fears for pink iguanas as Galapagos volcano erupts

14 hours ago

A volcano in the Galapagos islands erupted for the first time in more than 30 years Monday, sending streams of lava flowing down its slopes and potentially threatening the world's only colony of pink iguanas.

Ecologists develop new method for mapping poaching threats

May 22, 2015

Ecologists from the University of York, together with the Wildlife Conservation Society (WCS) and the Uganda Wildlife Authority (UWA), have developed a new method to better identify where poachers operate in protected areas.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.