Horse droppings behind alien plants dispersion in remote wildlandsNovember 25th, 2007 - 11:33 am ICT by admin
Washington, November 25 (ANI): A new study has revealed that wild horses are a source of the invasion of alien plants, which are rapidly becoming a threat to wildlands, in Colorado.
The study, published in Rangeland Ecology & Management, underpins the belief that large mammals trigger alien plants invasion by foraging for food in new locations and excreting seeds there.
Recreational trails in western wildlands represent corridors that connect the front country and the backcountry, and many trails are used by people with horses and other pack stock.
The large number of horses on public lands, and the potential for them to carry alien seeds, could make horses an important vector for alien plant dispersal in remote wildlands.
During the study, the researchers sampled horse dung along the first 4,000 m of the Lower Piney River trail in the White River Forest of western Colorado, which revealed 20 species and 564 seedlings.
The species were evenly divided between native and alien, but 85 per cent of the seedlings were alien.
Although the alien species in the samples were common species that are not a priority for management, the researchers said that the important result was that horses had the potential to disperse a large number of seeds from a wide variety of plant types.
With over 16,000 backcountry riders in the United States, a small decrease in the probability that the average horse will introduce a noxious plant into a public wildland could have a large influence on the ongoing invasion of native communities and ecosystems, said the studys researchers Floye H. Wells and William Lauenroth of Colorado State University. (ANI)