Animation of "Giant Reed" Plant May Speed Its
By Marcia Wood
August 19 2009
Along streams and irrigation canals in
16 states, a wily weed called giant reed, or Arundo donax, can grow a
remarkable 3 to 6 inches a day. This intruder crowds out native plants like
cottonwoods and willows, and can block water flow to farms and cities.
In research designed to stop arundo's advance,
Agricultural Research Service (ARS)
F. Spencer and co-investigators have developed a computerized,
science-based animation that shows precisely how a real-world arundo plant
grows. The animationapparently a first for an invasive weedis
intended for researchers, streamkeepers, students and others.
During this brief clip, a reality based "virtual arundo" goes
through its first year of growth, emerging from a single, thick, underground
stem, or rhizome, to reach its maximum height of about 30 feet.
The animation is derived from studies led by Spencer. In some of those
studies, thousands of digitized measurements were taken by magnetic sensors of
dozens of arundo plants. Using commercially available software, the
measurements were analyzed to create L-DONAX, a computer-based model of
arundo's growth, with optional 3-D animation.
Work to improve the first (2007) version continues. Meanwhile, the animation
has been newly posted on the web. To view it, scroll down toward the bottom of
Researchers can use L-DONAX and its animations to gaugeand see
on-screenthe predicted effects of tactics to control arundo. For example,
the model could help scientists determine the best times in the weed's growth
to unleash helpful insects that attack arundo's leaves, stems or rhizomes.
Spencer, who works at the
Exotic and Invasive Weeds Research Unit in Davis, Calif., created L-DONAX
with David Thornby, formerly at the University of California-Davis;
Jim Hanan of the University of Queensland,
Australia; and Anna Sher of the University of
Denver and Denver Botanic
Garden in Colorado.
ARS, the U.S. Department of Agriculture's
principal intramural scientific research agency, and the
Australian Research Council, Canberra,
funded the research.